Riser didn't know his fiancee was harassed by his previous fiancee. Even if he knew, he couldn't stop it since he wasn't in the domain of Sitri. Instead, he had returned to his family domain to search for a hot spring source with his peerage members and all the staff given by his parents.
As expected, he quickly found the source of the hot spring with his fire manipulation ability, which could help him pinpoint where most heat was concentrated in the area.
Previously, he thought of creating a geothermal energy plant, but the devil's world had better technology, so he gave up and quickly changed his plan to create a hot spring resort.
While it might be strange, it was common sense that where most heat on the surface of the earth concentrates, a hot spring would naturally be found. It was also the reason why Japan, which had rich geothermal energy, didn't create many geothermal energy plants since instead of being used as an energy plant; all the people favored making a hot spring resort.
Frankly, whether it was an energy plant or a hot spring resort, one needed to discuss many things before one could conclude which one was better, but for now, in the Underworld, the hot spring resort was something that needed the most.
With his guidance, the staff from the Phenex house also quickly secured the hot spring source with happy faces since they knew that this hot spring would boost the economy of the Phenex domain and all the devils who lived in the domain.
Riser also prepared many plans about this hot spring resort and decided to use many tricks to attract all the supernatural beings in the Underworld to visit this resort. Moreover, he didn't only find one of them; instead, he found quite a few of them, so each of them could be built with many unique themes from Japanese style, Western style, outdoor style, and many others.
When he had finished with all of this, he didn't do anything and just left the rest to the staff, enjoying the life of a noble who sucked dry the blood of his subjects.
[You have received "Mathematic Mastery"]
"...."
Riser was speechless, but he closed his eyes as much information about mathematics started to enter his head. He felt like he had become smarter, and his head became so clear. It was hard to describe his situation, but for one thing, he realized that he was an idiot in the past.
Though, frankly, if he didn't have a "High Intelligence," which he received previously, the process to accept this reward wouldn't be so smooth.
"Good work, Riser-sama."
While waiting for him to work, Ravel and his peerage members prepared a table for a picnic.
"Thank you for your hard work, Onii-sama."
They brought him a cold drink and food as they thought that he was hungry.
"Thanks."
He smiled gently and took a cold drink while observing the scenery in the surroundings.
The nature around them was so beautiful that it wouldn't lose to any nature wonders on earth in his memories.
This also raised his confidence in the success of this hot spring resort.
Still, he didn't forget to take a photo and video of the scenery of his surroundings with his phone before sending it to Sona.
While he felt quite moved by the success of his ability to find a hot spring source, the mood of the female who stood beside him was rather complex since they knew that after this, he would marry someone so quickly.
The change in Riser made them love him so much, and they didn't want him to marry right away, so when he divorced Rias, they thought they could monopolize him, yet the reality?
It hadn't been a month since his divorce, yet he was ready to marry someone again.
However, as his servants, they also knew their position well. While at night, he loved them so much that they couldn't pull themselves away from him; they couldn't act selfishly, asking him not to marry since, among devils, hierarchy was something that everyone upheld the most.
As his servants, they didn't have a right to question him, and they could only accept everything.
Yet, Ravel was different.
"Onii-sama..."
"What's wrong, Ravel?"
Ravel looked at her older brother with a complicated gaze. She was glad that Riser was single, but then, he was going to marry once again, and it was so soon that she couldn't react.
While their parents and older brothers were happy, Ravel found it quite difficult to accept this marriage since it happened so soon.
Suddenly, all of a sudden, she didn't have any preparation at all!
Yet, at the same time, she also understood that Riser didn't have a choice since this was something that everyone longed for, and his marriage to Sona Sitri would bring a great benefit to their family.
Yet... yet...
"Onii-sama... are you really okay with this marriage?"
She couldn't help but ask this question as if the one that was wronged in this marriage was Riser.
If it was before when Riser didn't change, then the one that became his fiancee would be the one that was harmed, but he had changed, and he was also the third son among the three brothers.
Whether it was Phenex's first or second brothers, they had married, and they all married high-ranking pure-blood devils.
Even if Riser chose to marry someone with a lower status, no one would blame him, but he accepted his marriage with Sona.
This marriage... no matter what had to be succeeded.
Even Ravel knew that, yet... yet... she still couldn't accept it as she thought that he was forcing himself to marry someone.
Facing this question, he smiled gently at his little sister and tenderly rubbed her soft blonde hair.
[There is a rare mineral mine cave nearby. You can bring Ravel there and make her join your harem]
"....."
The smile on his face was slightly stiff, but he was also dumbfounded since he didn't expect there would be a rare mineral mine nearby.
While this system asked him to do something immoral like how a real satan did, the benefit was incredible.
"Are you worried about me?"
"O-Onii-sama..." Ravel was shy, yet she also enjoyed the way he rubbed her head, but at the same time, hearing his question, she nodded. "I-I do. I don't want you to have the same experience again. I-I want you to marry someone that you really love..."
Suddenly, a forbidden thought emerged in her head, causing her face to turn red like a blazing flame.
"Ravel..."
He felt complicated since he could tell that Ravel really cared about his well-being as his little sister, yet he always thought something strange inside his head. While it was partly the fault of the system, it was hard to see her as a little sister, especially when he wasn't the real Riser Phenex.
Still, when he was about to answer her, suddenly, he noticed an enormous figure coming from the distance.
He raised his head and looked at the distant purple sky.
"Onii-sama?"
When her older brother was in silence, Ravel also looked up, but she saw his attention was somewhere.
Similarly, others also followed his eyes and became confused.
"What is that?"
They could see an enormous shadow moving toward their direction before they widened their eyes since they saw Ziz, a giant bird in Jewish mythology.
"Huh?!"
They lost their calm since the appearance of this monster destroyed all their calmness.
"Calm down."
His voice was like magic, and they quickly looked at Riser, who had risen to the sky, facing Ziz directly.
Meanwhile, Riser was confused, and he also noticed a small presence that stood at the head of the Ziz.
"The one that brings peace and smiles to the Underworld!
"The destroyer of Angel, Fallen Angel, and all the beings that threaten the Underworld!
"Bringing a smile and hope to every Devil!"
Suddenly, a cheerful BGM, along with a powerful yet feminine voice, echoed through the space, causing everyone to be in a daze. When they were confused at the source of this commotion, a figure jumped from the top of Ziz's head and landed in front of everyone, facing Riser as if he was the greatest enemy that had intended to destroy the world and bring danger to the devils.
"I am Miracle Levia-tan!"
Miracle Levia-tan stood with a cute yet powerful pose as she pointed her magical stick at Riser.
"Phantom Phenex! I have come to stop your conspiracy! Give up useless resistance and be beaten by me!"
"..."
Everyone was in silence, and they had a similar thought in their minds.
While she appeared cute, the words that came out of her mouth weren't cute at all.
---
I wonder what kind of BGM will be suitable for Serafall.