Demonic Union

(Yukio): "You're late, Nii-san."

After parting ways with Natsuno, well, I guess Tsuno now, and Vepar, I walked back to the old boys' dormitory in a daze. What was waiting for me at the entrance was Yukio who was looking at me with a stern gaze. Oh crap, he's usually back late thanks to his exorcist work so I didn't bother telling him I'd be out late. This might get annoying.

(Rin): "Sorry, I was hanging out with a senpai today."

I said with a nervous smile to Yukio as I felt a little bad for not mentioning this to him. I should try getting along better with him, but he's always busy with work or his role as a student representative. I even suggested helping him out with his school work but he still sees me as the same unreliable older brother. I need to change that image in his head.

If I beat him at the end of term test, I wonder how he'd react to it? Would he be happy for me or would it damage his ego? Probably both to be honest.

(Yukio): "Oh? Might I inquire which senpai this was with?"

Yukio asked me as he adjusted his glasses. The vibe he was giving off was like getting questioned by a school president or a public moral committee member for not following the student code. My lips twitched from the comparison I made.

(Rin): "Sure, her name is Natsuno Kirihime. She's from the Culture Club. We got some concert tickets from an event she won so we used them to hang out and stuff."

I told Yukio as I felt like I got caught doing something that I was told not to do. Well, it's not like I'm not allowed to hang out with others, but he's technically my supervisor and all. I feel like he'd make a hissy fit if I told him about it anyway.

(Yukio): "So a female senpai…"

Yukio says to himself as he puts his hand into a thinking pose. Oi, stop thinking right there Sherlock.

(Rin): "Before you jump the gun, we were there as friends."

I interrupted his train of thought when I figured he was going to misinterpret what I meant. It's annoying if other people misunderstand our relationship when I haven't gotten the stuff in my head sorted out yet. The fewer headaches the better is my thought process right now.

(Rin): "And even if it was a date, I can date whoever I want to."

But even then, I don't want there to be a misunderstanding between us. I don't want Yukio to control me in terms of if I'm able to date someone or not. My mother was like that after all. When I entered secondary she told me to not even think about dating anyone or bringing people to the house. Because if I did then they'll find out how twisted my mother would be and how bad the living area is. 

I guess I still got the trauma of being controlled like that.

(Yukio): "Haaah, I understand. I was just a little worried for you. At least tell me when you're going to be back home late. I had to ask the kids to find out."

Yukio says with a little smile after a sigh. Dude, you worry too much for me but I can understand why he feels that way. It's just like how I worry about my kids so I can't criticise him much. I just nodded in response since it was my fault for not telling him. He must feel conflicted or something since everyone else in the dorm knew.

(Yukio): "Alright then, go to sleep after washing your face and cleaning up."

(Rin): "Alright mum."

I said in response to Yukio's words before walking into the dorm and headed to the bedroom. Yukio went too, but he ended up studying instead of sleeping. How does he juggle his exorcist work with school stuff? He's not even sleeping that well. He always wakes up before me then disappears. Sometimes he even skips breakfast entirely.

I looked at his concentrated face as I wondered what I can do to make things less awkward between the two of us. I want to get close to him. Thinking of such without much of a plan, I got up and started doing my homework next to him. He looked at me and didn't say much as we sat in silence doing work.

(Yukio): "Good work today. I'm going to go to sleep now."

(Rin): "Ah alright, good night man."

By the time I realised it an hour passed by quickly and Yukio was done with his work. Jesus, I'm not even halfway done with mine. I carried on until I hit the halfway mark before going to bed to call it a night. I could already hear Yukio snoring lightly and my kids, who are usually early sleepers, have been asleep even before I entered the room. I headed to my bed once I fixed Midori's sleeping posture.

There's only one problem though. 

(RIn): "I can't sleep."

That kiss from Tsuno was still on my mind. Even with the conversation I had with Yukio and doing my homework, it wasn't enough to fully distract me. The feeling of her soft lips kept replaying in my mind as my heart kept pounding like crazy. Feeling as if it would take a while for me to calm down, I went to the pocket dimension to think a little.

As someone who was a loner in his past life, I didn't have much contact with girls. So the kiss was a big surprise to me since I'm not used to affection or girls in general. It's not like I'm allergic to girls or anything, it just makes me feel nervous and embarrassed even though my face would show otherwise.

To be honest, it had a bigger effect on me compared to when Akane kissed me after I saved Naneko from her inner demon. I guess Akane had a reason, but Tsuno did it out of nowhere to me. I'm not sure if it's because of her lack of distance awareness or if it's genuine affection. It could even be her way of saying thanks that I'm not aware of. But doing that still made me feel embarrassed.

(Rin): "Haah, girls are confusing."

I said that as I practise some martial arts. It's not like I'm bad at talking to girls like I was before. I've gotten a lot more confident with myself and talking to others too. But some of the girls' actions confuse me. Like Akane going along with my kids "Mumma" mission and how she dragged Naneko into it.

I don't know how others see it, but from my perspective I just see the two of them messing around and not wanting to hurt the kids' expectations. It's not like they're serious, right? If I misunderstand her for being serious when she's not, then that makes this weird relationship break, wouldn't it? I feel a little conflicted.

Of course, I'd joke around with it, but I don't think they're being serious. I don't know, now I'm starting to feel conscious of the girls. It sounds like a harem anime now that I think about it. Should I stick to how I was before and ignore what the girls are feeling or confront them directly?

I honestly have no fucking clue what to do. How do I interpret all of these signs! Someone fucking give me some help here!

(Rin): "Why are girls harder to understand than an entire mythological history textbook?"

I sighed to myself as I did a backflip then a roundhouse kick to finish off my martial arts training. It's been two hours so far, but only a few minutes have passed in the real world. For me, this wasn't tough at all but my form still needs some tweaks. It's only after spending this much time training did my head feel a little less clouded.

Seriously though, I feel like studying an ancient textbook or researching an ancient civilisation would be easier than understanding a girl.

(Rin): "How… Does one even love?"

I sighed to myself as I felt a little lost. It's not like I don't know what affection between family members is. Although it was a long time ago, I experienced it with my grandparents and I felt that same affection, or something similar, when I interacted with my kids. So familial love is something I understand but… the love between man and woman? It was only after coming to this world did my heart start fluttering when I interact with girls. In my past world, I didn't care at all about girls or romance but that might've been the effect of my mothers' constant abuse.

So far my heart has been shaken by Akane, Naneko, Tsuno, Sora, Chelsea, Shiemi, Izumo and even Noriko. Basically most of the girls I know. I'm an easy guy, aren't I? I always try acting like a straightforward guy when I interact with them, but that's only to hide my embarrassment. If it was the old me, I would've been too nervous to look them in the eyes, so to cover it up I'd have a blank face or something and pretend to not know them.

It's not like I wasn't interested in girls in my past life. I... Just felt apathetic to a lot of stuff during that time. The only thing that I cared about was my safety and watching anime or reading manga to maintain my sanity. Irl girls just… felt fake? I don't know. I'm still trying to understand myself. After coming to this world I got myself the original Rin's side of emotions and my old ones revived. I got to experience a bunch of stuff thanks to this transmigration. I met a lot of people and had so much fun.

That's why another thing is worrying me. Apparently, I have another soul in me as well as two inner demons. In the manga, Rin had only one inner demon that appeared when Amaimon broke Kurikara. The original RIn might still be in me, but dormant or something. I don't like this kind of cliche within fanfics, but the other demon is what's making me curious. What reason do I have another demon inside me? I can think of some theories but I don't want half of those to be real.

And speaking of emotions, I've noticed that I have a weird sadistic tendency of toying with people and demons lately. I thought it was because I was angry at them and wanted to make them have a taste of their own medicine but I have a feeling it's something more than just that. Could it be the effect of being raised by my mother or because I've been releasing my demonic side too much lately? Maybe even having two demons in me could be a cause. 

(Rin): "I guess there's not much to do for now but see what happens in the future. Unless I find someone that's a soul specialist there's no reason to worry about it too much since I can't do anything. As for the harem, if it does form, I won't push anyone away. I don't think I'm capable of doing that. The law would only be a problem."

Unless we somehow make polygamy legal? Or if the girls are fine with not getting married? But the public opinion would still get in the way. Well, at least the opinion of the people around us. I don't care about gossip, I'm already used to it from my past life, but that might affect the girls mentally after a while. I don't want to hurt them either.

(Rin): "Huuh, I'm getting ahead of myself. Before I even think of a harem, I should develop my relationships with the girls and even my friends better. Try bridging the gap a little."

I shook my head and sighed. It's not the best of plans, but it's the only thing I can do. Whether a relationship forms between us, who knows. For the time being, I'll work on those and see how the future plans out.

>\/<

After finishing another training session that lasted 5 more hours, I finally felt exhausted enough to go to sleep. I was sweating pretty badly so I burned my sweat with my flames before heading directly to bed. When I woke up, my body was burning from the muscle pain that was coming all over. I guess I took it too far again.

(Rin): "Morning Kiddos."

I said with a yawn before looking at the children that are on top of me, giving me an early morning hug. I get this usually whenever I sleep in. When I checked the time in my head, it was only half-past 5. That's unusual, it's early.

(Midori): "Morning Pops."

(Kage): "Good morning Tou-san."

(Kuro): "Mornin' Dad… zzz..."

The kids greet me as I give them their morning head pats. 5:30 is too early for them to wake up. Did something happen? Kuro usually sleeps in till it's 10 or even 11 am, Midori and Kage are usually easier to wake up, they wake up around 9 am.

(Rin): "Why are you guys awake so early?"

I asked as I got up before looking over Yukio's bed. He's already gone and made his bed huh. What's his sleep count like? Must be 4 hours or something, it's ridiculous. He was still here when I got back from the pocket dimension.

Maybe we'll have breakfast together another day.

(Kage): "Natsuno nee-san is waiting at the cafeteria."

Kage says with a little yawn as she rubs her eyes. She's wearing one of Akane's skull t-shirt which is clearly oversized for her and some shorts. She's been copying Akane's sleeping habits recently, I pray she doesn't develop Naneko's habits too… 

(Midori): "And Sorano nee-san was with her before she left. I think she's off for a run."

Midori says as he jumps off the bed and performs a handstand. He's been getting into acrobatics lately and does stuff like this whenever he gets the chance. Guess it's thanks to his school. He's wearing a green PJ he's been liking recently.

(Kuro): "We woke up when we sensed them... We didn't want to wake you up so we just waited… zzz"

Kuro says with a sleepy expression and half-open eyes. Heh, he didn't want to wake me up but he's tired as hell. I felt warm for the cat boy in front of me as I messed with his head. As for him, he's wearing a blue PJ onesie.

(Rin): "Ah, thanks, you guys. I'll treat you to something later today."

I say with a smile to reward the kids. I keep forgetting that these kids have better detection skills than I do. It comes in handy a lot.

(Kuro/Kage/Midori): "Yay!"

The kids celebrate in joy from hearing the reward. Kuro finally woke up because of it and Midori did a front flip as they all jumped around to celebrate. These little guys' reactions are too cute whenever a reward gets mentioned. I wonder what I should make today?

(Rin): "Oh yeah, come with me. We got a surprise coming."

I say with a smile, remembering what's going to happen today. Although the stuff that happened yesterday had me confused and conflicted, today's a new day and I feel refreshed. Maybe another long training session would do me good?

(Midori): "What is it? An announcement?"

(Kuro): "Marital status update?"

(Kage): "Maybe a new snack recipe?"

(Rin): "Just wait and see."

I said as I smiled wryly at my children's answers before we went to the cafeteria to find Tsuno who's waiting. They give troubling answers as always. While we were walking, the kids started talking about what the surprise would be.

(Midori): "What do you think the surprise could be?"

(Kage): "I hope it is a new snack recipe."

(Kuro): "You'll get fat if you have too many sweets though."

(Kage): "I am not talking to Kuro Onii-san anymore."

(Midori): "Yikes, you took it a little far nii-san."

(Kuro): "Haha, sorry Kage. I'll give you my share as an apology."

(Kage): "Apology accepted."

(Midori): "Nice recovery."

(Kuro): "That was a close one."

(Kage): "Hmm, Otou-san looks excited."

(Midori): "Yeah, I wonder if he's happy to see nee-san?

(Kuro): "Hmm? Could she be a potential Mumma? He's finally making progress!"

(Midori/Kage): "Ah, I see!"

(Rin): "You kids really…"

I just sighed to myself at the kids' antics. Their conversations always change like that with just a finger snap. I don't get why they get so annoying when there's a girl that gets mentioned. They remind me of the comment sections of some old novels I'd read where the readers would scream "Harem member spotted!" or something similar.

I got sidetracked again. I'm excited though but only because I get to learn a new skill. Tsuno mentioned to me that she can't use her powers to the fullest extent without merging with Vepar, meaning she can still use some of her powers even without the fusion.

I figured that if that's the case, I might be able to pick up some kind of ability from my kids during the process, or maybe at least a passive skill. I love my flames and all, but I'm still intrigued by the idea of gaining more power, even if it's limited and can be used under certain conditions. I guess that's the inner geek in me's fault.

(Natsuno): "Morning Rin, children."

When we got to the cafeteria, we found Tsuno sitting on one of the bean bags reading a book. Was she prepared to stay over here for a few hours till someone wakes up?

(Kuro/Kage/Midori): "Morning/Good morning!"

(Rin): "Morning to you too, Tsuno. You're here pretty early."

I respond as I question why she's here this early. We could've done it in the afternoon or something around that. Was she gonna wait till 9 am or something for everyone to wake up?

(Midori): "Hmm? Nicknames huh."

(Kage): "Looks like Kuro onii-san's words were accurate."

(Kuro): "Hehe, told you so- ow!"

(Rin): "You brats talk too much."

Hearing my words to Tsuno seemed to have triggered the kids' teasing side. I hit the cause of it on the head before he starts bragging about it. I swear, why did they have to pick that up from us…

(Natsuno): "Seems you get along well with your children."

(Vepar): "This one still sees a violent brute. We got here since Lady Tsu's an early waker and was worried when to arrive so she decided the sooner the better."

Tsuno said with an amused look on her face as Vepar suddenly appears and sits on top of her book before answering my question. Eh, this is taking it too far though. What time did she wake up for that anyway? She and Sora are crazy to wake up before 5 am...

(Kuro): "A mermaid?"

(Kage): "A chibi version of Nee-san?"

Kuro and Kage asked out in curiosity of the new person. Heh, told you it'd be a surprise.

(Midori): "Another one? No wonder fathers hap-ouch!"

(Rin): "You kids need to watch your mouths. I can't wait for when karma hits you."

I head chopped Midori as I shouted at them a little. I swear, if I ever see these kids with the opposite sex, I'm going to roast the hell out of them. These kids need a taste of their own medicine.

(Vepar): "Haha, even though you're a brute, your hits don't have much power behind them. It seems like your kids enjoy your company too."

Vepar says with a smile to the kids and gives me a gentle look? I guess kids are her weakness huh. Might be something I can use to tease her with.

(Rin): "I guess I'll take that as a compliment. Morning to you too, Vepar."

I said with a wry smile before Tsuno finally closed her book which made Vepar get forced to float now. Her species of demon interests me a lot. She's too different from the others.

(Natsuno): "Shall we start the Union?"

(Kuro/Midori/Kage): "Union?"

The kids' ears puckered up from hearing a new term as they cutely tilt their heads to the side. I have a feeling that they're going to get interested in this too.

(Rin): "We're learning a new technique. It's gonna let us fuse with each other temporarily."

(Kuro/Midori/Kage): "Oooo/Aaah/woooh."

The kids looked at Tsuno with sparkling eyes from the words of a new skill. I knew they'd be excited, they love fighting after all. We all took our seats at the table, with Tsuno sitting at the head of the table to begin the lesson.

(Natsuno): "To start off. Demonic Union is similar to a demon possessing a human."

Tsuno says as she wears a pair of glasses. Where did she get time to get that from? They suit her.

(Vepar): "The regular possession either takes over a person's body or a part of their body."

Vepar then explains as she also wears a pair. How'd she get one her size… Anime logic. 

(Natsuno): "Demonic Union is a technique used in the 72 pillars that are naturally able to perform where they coexist with the host."

(Vepar): "But unlike the normal possession, it's only a pseudo possession to use their powers. Doing such lets us use more of our powers as we're a different type of demon where we don't need a host to roam in this world."

I thought so. That's what I meant when I said she was an interesting type of demon. Most demons possess an animal or something in order to interact with our world. That was the same for my kids after all. Kuro was a cat that gained intelligence after a hundred years so he's a different case, but Midori's species possess mice and Kage's possesses dust.

It's convenient that Vepar's species don't need a host to live over this side, but even that has its limits it seems.

(Natsuno): "But there are side effects. Like this."

Tsuno says before a small miasma circle appeared and her cup of water became ice. The kids looked at her in surprise and admiration as they listen to her words.

(Natsuno): "I can use a small-scale version of Vep's powers and immune to cold when it goes below a certain limit."

Tsuno says that before reverting the ice back into water again. Oh, she can do that while her power is limited? Still, it's interesting to see a human be able to hold miasma in their body. I wonder what the limit her body can handle is?

(Midori): "Ah, No wonder your name sounded familiar! You're from Solomon's 72 pillars, aren't you?"

While I was interested in Tsuno's powers, Midori seems to have remembered Vepars name's origin. Looks like studying mythology with him has paid off.

(Rin): "Nice deciphering, but how'd you figure it out? Their abilities are different even if the names are the same. "

(Midori): "Hehe. I've seen some variations where they use ice powers and thought they were linked. It was a light novel a friend of mine gave me."

(Kuro/Kage): "Good job."

We congratulated him as I gave him a head pat. I feel proud of his thinking, like a dad hearing of his children's good grades. I wonder what's the source he read though, I should read them just in case.

(Natsuno): "Yes she is. To use Veps powers, she possesses the tattoo on my stomach."

Tsuno says that as she lifts her shirt again to show off her tattoo. Hmm, I don't think she's eaten, has she? Guess I'll have to make double the usual amount of food for breakfast.

(Kage): "Ah, beautiful."

Kage was the only one to react as the others had eyes of curiosity for the tattoo before looking at me. Guess they're thinking where I'd have mine if I do the Union skill.

(Natsuno): "Thank you."

Tsuno replied before she suddenly had a red face and put her shirt down. Looks like she realised that she was being too revealing again.

(Vepar): "The tattoo is permanent for the 72 pillars due to special circumstances."

(Natsuno): "It shouldn't be permanent for you."

(Vepar): "It would only appear when you're fused or use parts of their powers."

Oh damn, I didn't think about the tattoo part. I guess I don't mind as long as I can hide it, but it being permanent is a little troubling. Luckily the academy doesn't care about tattoos but I don't want to be seen as more of a delinquent than normal. It gets annoying...

(Natsuno): "Now, to begin with, Demonic Union requires trust between the pairs."

Oh looks like we'll be getting into the juicy parts now that the introduction is over.

(Vepar): "As both of you will be sharing a body. If you experience any pain, the demon that shares its senses will feel it too."

(Natsuno): "And in some cases... Where the host dies, so does the demon."

Tsuno had a dark expression when she said her part and I noticed that she clenched her fists. Did she have to kill one of the pillars in the past or something? The girls outside of canon are a lot more mysterious than I thought.

(Vepar): "That's only the first step. You must maintain a stable mind otherwise the Union would forcefully exit. There are some cases where a weak body wouldn't be able to handle the miasma as well, but for a demon such as yourself to be in the conjurer's position of the Union, it should be interesting."

Hmm, since I'm already a demon, well a half-demon, I wonder if there'd be any different effects as opposed to a human? I wonder if my flames would interfere with it?

(Vepar): "But as it's between two demons, the technique is a little different. Once you learn the breathing techniques you must both mark each others miasma in order to freely fuse with them. Otherwise, it's possible to have one demon that can be used as a host. But they won't be able to fuse with the other demon if that makes sense."

Oh, so it's possible to have Kuro fuse with Midori and vice versa huh. I like that idea a lot now.

(Natsuno): "We'll practise breathing techniques for now."

(Vepar): "Ah, we forgot to mention affinity also affects the Demonic Union. Don't feel bad if it's not possible to fuse, but you may be able to fuse with your siblings so try that out if possible."

Vepar gave us some reminders and advice before we started learning some of the breathing techniques for the Union. It wasn't that hard to learn but matching my breathing with the kids was the difficult part. 

The Union skill was a lot harder to learn than I thought to be honest. Oh well, no pain no gain.

(A/N: Alternative Titles: "Rin's thoughts", "Morning demon lesson", "I wonder what skills will Rin gain?")

(E/N: Rin just do what all good harem mc's do, use how dense you are to pull girls to you.)

Edited by Xenoblade

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