To become strong, a sacrifice is necessary

"Liar~! Masa-chan is a liar~! If he misses me so much, then you will answer my call every day~! You haven't called me for so many days before~! I am so angry~! Hmph~! Hmph~!" 

"....." 

Masa was at a loss for words, wondering how a woman hundreds of years of age could act like a little girl, but then again, this was why he decided to become closer to Serafall Leviathan among all the existing Four Great Satans or Maous. 

Sirzech Lucifer, Ajuka Beelzebub, Falbium Asmodeus, and Serafall Leviathan. 

Those were the Four Great Satans of the Underworld and were also the four strongest devils in the world. 

Why Serafall? 

Was it because she was a beautiful woman? 

Masa wasn't so shallow, okay? 

It was just according to his original memory; he knew that among all the Four Great Satans, Serafall was the chillest, gentlest, and the least troublesome. 

Yes, she might be weird as she had this strange obsession with a magical girl, but it was okay compared to the others. 

Sirzech Lucifer might be the strongest, but this one was strangely idealistic and wanted everyone to follow him even though it might not bring the benefit to the group, and he wanted to have absolute control over those who followed him, which was troublesome, Masa thought. 

Ajuka Beelzebub was good, but it was hard for Masa to meet Ajuka, and even if he was able to meet him, Ajuka might not even have an interest in him, considering this guy was so obsessed with research and talking with others, simply wasting his research time. More importantly, Masa didn't have a talent for technology before, so he simply gave up getting close to Ajuka. 

Still, to be honest, Ajuka wasn't someone that Masa could trust, especially considering how coldly Ajuka treated his family, considering how Ajuka didn't care about the death of his little brother. 

Even if this little brother was evil, shouldn't Ajuka show some of the cares? 

Regardless, Ajuka wasn't good, Masa thought. 

Then, what about Falbium Asmodeus? 

This guy was a sloth, and Masa even heard this guy's quote, saying, "Working means losing." 

If Masa got close to this guy, he was afraid that his busy day would be even more busy, considering he could imagine Falbium throwing all of his job to him. Still, his relationship with Falbium was quite good, considering his relationship with his niece was good. 

Yup, Masa was quite close to the house of Glasya-Labolas, which was a house in which Falbium originated. 

Still, among the Four Great Satans, Masa had the closest relationship with Serafall, especially due to his media monopoly and his help in promoting Serafall's show, Miracle Leviathan. 

Frankly, he didn't care whether this project made money or not, especially when he just wanted to get used to this show to get close to Serafall, but fortunately, this show made money and became so popular in the Underworld, so it was all good, he thought. 

Then, had he ever thought to get close to Serafall? 

To be honest, Masa would be lying if he didn't, as Serafall was a beautiful woman, and even if she was much, much older than him, she appeared like a charming young woman, so how could he not be attracted? 

Yet, considering his strength, Masa decided to be a realist and chose someone that he was close with instead of Serafall. 

Even though Serafall was quite old, she was still single and didn't even have a male presence by her side.

Why was that? 

Masa wasn't sure, but having a woman with a past was troublesome as there might be something hidden that made their situation troublesome, so after he became a little older, he also tried to change their relationship from being too close to being formal. 

Yes, in many stories, there was no doubt that Serafall was one of the targeted heroines that should be taken down by every MC, yet this world was no longer a fiction to him. 

The world of DxD was his current reality, and naturally, the reality was different from fiction as many complicated feelings made it hard for one to express their feelings. 

Still, the most important thing in this world was strength, so instead of heroines that he could get any moment, he should think about how to increase the weight of his Ton Ton no Mi further, at least to have a similar weight to Mount Everest. 

Or, the weight of the star, so he would become the center of the galaxy. 

"I am sorry, Serafall-sama. I have been busy with many things." 

"Onee-chan! Call me Onee-chan like before, Masa-chan!" 

"...I am not young anymore, Serafall-sama, and it is no longer appropriate for me to call you in such a casual way." 

"Cold~! So cold~! I thought that it was only my ice ability that made me cold, but Masa-chan has become cold, too~! My little lion cub is in the rebellion period~! Huwaaaaaa~!" 

"..." 

Masa rubbed his right ear helplessly, then called Serafall the way she wished to be while feeling a little embarrassed. "O-Onee-chan..." 

"...." 

Strangely enough, Serafall was in silence after Masa called her that.

"Onee-chan?" 

"...by the way, Masa-chan." 

"What's wrong?" 

"How old are you now?" 

"Er... I am in the first grade of high school now." 

"Hmm... is he old enough? No, it should be enough, right? I have been for so long..." Serafall was in deep thought. 

Masa decided to call Serafall as she fell into silence all of a sudden. "Onee-chan?" 

"Nothing~! Anyway, what's wrong, Masa-chan? Do you want to join my show again like before?" 

"...can you not remind me of that?" 

Masa let out a helpless sigh, thinking of the sacrifice that he had made to get close to Serafall, which made him speechless. 

"You were so cute at that time~! My little lion cub's acting is so cute~!" 

"...I am no longer a lion cub." 

"Oh~? Have you become a great lion now~? Let Onee-chan see your growth in a week~! Onee-chan will come to visit your domain~!" 

"Ah, no, it's okay." 

"What~!? Don't you miss your Onee-chan~?!" 

"I miss you, but...you are a Maou Leviathan, after all. Shouldn't you be busy with many things?" 

"It's fine. I should have time this week, and I can even check your theme park plan, right?" 

Yup, to make the best of Miracle Leviathan's show, it was natural for him to create a theme park, especially with his media company; he didn't lack a copyright of many famous works and characters, so he decided to be bold. 

There was a chance of him failing, but this was how business was, right? 

Nevertheless, there was no doubt this act of his investment boosted the economy of his domain. 

Still, if this plan was successful, then there was no doubt the House of Sitri would be the next one, as it was the house that Serafall originated from. 

As for why Masa didn't build this theme park in the domain of the House of Sitri first, it was because, frankly, he wasn't that close to the House of Sitri, and as he had said before, he didn't want to get involved much in anything that was related to Issei previously when he lacked power, so while he was close with Serafall, he wasn't close with the House of Sitri. 

Moreover, as he had said before, no one was sure whether this plan could succeed, and the investment was relatively huge, so everyone waited to see whether this plan could succeed or not. 

Nevertheless, this wasn't the reason why he called Serafall since there was a reason why he called her, even if he usually called her to ask about her condition and many other things. 

"Okay, then I will prepare your favorite snacks." 

"Um~! I can't wait~!" 

"By the way, Onee-chan, can I make a request?" 

"...is it a pervy request? Masa-chan has really grown up, huh?" 

Could he? 

Still, Masa wasn't sure whether this woman was joking or not, so he thought to wait until they met. "Can I have permission to go to the human world?" 

"..." 

"...what?" 

"Can I have permission to go to the human world?" 

"Huh?! Masa-chan wants to go to the human world!"