Issei had wasted an entire day because of Rias Gremory, and the next day he went to school as if nothing had happened.
"She's not here today."
When he jumped to the old school building, Rias, who had been waiting for him like a mail carrier, wasn't there. It should have been natural, but now that she was absent, he felt strangely empty. At lunchtime, too—
"I'll eat with Matsuda and the others today, I guess."
—he went to the classroom, but she still didn't show. Even after school—
"Senpai~ Are you there?"
—when he went to the club room, there was no one there.
"Did something happen?"
In the end, just in case, he activated [detection mode], and—
"She's gone!?"
He couldn't sense Rias's presence anywhere in the city. A hundred possibilities flashed through his mind: maybe she'd been dragged home because of yesterday, maybe she was being punished, and so on. To find out the truth, he started looking for the other club members, but none of them could be detected anywhere in the city. That meant there were only two possibilities: either they had returned to the underworld, or they were inside some special barrier that blocked detection.
"I don't know how to get to the underworld..."
Then the only thing he could do was release all his shadow clones and search the town for any barrier-like structure spread across it. Or rather—
"Rias isn't in the underworld, Hyoudou Issei."
"Student Council President!?"
Suddenly, a black-haired girl wearing glasses appeared in front of Issei. She was Shitori Souna, the Kuoh Academy Student Council President, an upper-class devil like Rias, and a friend of his. Since Issei had only heard a little about Souna from Rias, he didn't doubt her identity.
"What do you mean by that?"
"Rias is currently away at a training camp for a Rating Game."
"A Rating Game?"
A Rating Game was a game devils played to compete in strength or wager something on the outcome. And the fact that it was being held so suddenly meant something had happened to Rias.
"Why is Senpai in a Rating Game?"
"That's..."
Souna seemed to find it difficult to say.
"I was told not to tell you because it would only make you worry unnecessarily, but Rias has a fiancé."
Souna kept speaking. The Gremory family, to which Rias belonged, was one of the great noble houses of the underworld that valued pure blood. And after the great war in which the Two Heavenly Dragons rampaged, the underworld had lost nearly all of the former Four Great Satans and pure-blood devils, so among the high-ranking devil clans, arranged marriages for the sake of preserving pure blood were the norm. Rias's family, the Gremory family, and the Phoenix family had promised an arranged marriage between them. Now that the time for that promise had come, Rias had strongly refused after receiving the notice from Grayfia the previous evening, but her objection had not been accepted, and in the end it had been decided through a Rating Game. Hearing this, Issei's face darkened, and he clenched his fist tightly.
"Could you tell me where that guy named Raiser Phoenix is?"
"It would be better for your own safety if you stopped. No matter how special you are as a human, your opponent is an upper-class devil from the Phoenix family, a so-called immortal. You should know without me saying what would happen if you laid a hand on him."
"No problem. Tell me."
"You... what are you planning to do?"
If he answered, "I'm going to wreck the place," she would obviously never tell him for the sake of underworld order. So—
"I'm just going to talk to him. If I can persuade him."
"Sorry, but there's no way human words will reach Raiser Phoenix..."
As expected, even Souna, who was more favorable toward humans than other devils, still regarded them as inferior beings. But Issei was different from ordinary humans. He possessed the [Rinnegan] and had the [Ten-Tails] within his body; in other words, he was an existence on par with the Sage of Six Paths. And with that power, he could even force the answer he wanted from the devil in front of him. But hurting someone for another person's sake went against Issei's principles, if he even had such things at all. In other words, he didn't lay a hand on beauties with big breasts. That was all. (Exceptions applied to those who tried to kill him.)
"But if I don't try until the end, I won't know, will I?"
"Do you really think I'd send a human off to commit suicide? For Rias's sake, absolutely not."
"Then why did you tell me all this in the first place!?"
He couldn't understand why she had brought up Rias at all if not to make him go and cause a scene. The only thing he could think of was that she was telling him not to cling to a friend as a mere inferior human.
"Could it be... you don't like me hanging around Senpai?"
For once, Issei's tone was seriously unlike his usual self. Souna stared at him for a moment, then sighed.
"Do you still not understand? Only devil servants are allowed to participate in a Rating Game. If you care about Rias that much, then all you have to do is become a devil yourself and join the Rating Game."
"Me... become a devil?"
From the beginning, he had hated the idea of giving up being human, so even after Rias's persistent invitations, he had refused until the end. But that had only been because, on a purely personal level, he wanted to remain human. And whether he became a devil or stayed human, the important thing was his own will, but—
"I'm the one who will serve as referee for the match between Rias and Raiser Phoenix. And the chance of Rias winning is less than ten percent. The Phoenix family is trying to force her into marriage against her will. I... don't want to see my friend married off so miserably either. But if you stand with Rias, her chances of winning will rise even a little. If you want to stop Rias's marriage, then accomplish it yourself."
"Why would Senpai have to go through something like that..."
Once he understood everything Souna had said, what he couldn't accept was not Souna's opinion, but Rias's situation. Born as the daughter of a high-ranking family in the underworld, destined to become the next head of the house, and yet being forced to marry someone she didn't even like—Issei, who had already experienced the end of such a marriage up close, could not let Rias be married off like this.
"But..."
Honestly, if he looked at it objectively, she was just a senpai, and he was just a kouhai. They had only recently started meeting more often, and it wasn't a relationship worth risking his life for. More than anything, Rias had been meeting Issei only for information, so a normal person would have hesitated for a moment and gone his own way. But Issei could not forget Rias's face from that day. He remembered how sad she had looked, as if the moonlight streaming through the window were the last light she would ever see. And yet he still didn't want to become a devil. He wanted only to remain human, and in the end, ideals and reality began to collide.
"I..."
"I won't demand an answer. In the end, the choice is yours. Well then."
Leaving the decision to Issei, Souna walked out of the room. If an outsider saw it, it was a rather selfish decision. She did nothing herself and simply pushed the choice onto someone else. She knew that better than anyone, but she was someone who could never do anything that would harm her family.
"Rias, this is all I can do for you. Even if I end up taking the role of the villain..."
Thinking that this couldn't continue, she steeled her resolve as well and left the old school building.
.
.
.
.
.
"What am I supposed to do..."
The Rating Game was five days away. Since hearing about Rias from Souna yesterday, Issei was still agonizing over it. He couldn't reach an easy conclusion. Should he abandon himself and choose Rias? Or should he ignore the sad expression on Rias's face and protect himself? In movies, when people saw this kind of situation, they would naturally say, "You idiot, of course you should throw yourself away for the person you cherish." But that was the talk of a foolish child from long ago. Now that it was right in front of him, it was a serious problem. So, unable to choose either way, he wandered until he ended up at the one place that gave him peace of mind: the church, where Asia was.
"Issei-san, are you all right?"
"Asia... it's nothing..."
Asia worried over the dark look on Issei's face. He wanted to ask her what choice he should make, but he didn't want to burden Asia with something that had nothing to do with her. And then—
"If only I knew how to get to the underworld..."
"How to get to the underworld...? I think Raynare-san would know..."
"Eh? Really?"
"Yes. I heard that angels and fallen angels have a way to get there."
"Thanks, Asia! As expected, you're my angel!"
"E-eh? Th-that's... it's embarrassing..."
Unintentionally having helped Issei greatly, Asia blushed at his embrace and looked embarrassed. Then Issei headed to Raynare, who was sensed in the bed inside the secret room.
"Raynare!"
"Eh!? I-I didn't do anything, okay!?"
When Issei suddenly opened the door and came in, she hurriedly hid something and gave an awkward smile. But Issei didn't care at all.
"You know how to get to the underworld, right!?"
"Eh? Why are you suddenly asking about the underworld?"
"Just answer me, you do know, right!?"
"Y-yes... I do know, but..."
"Good. Take me there right now."
"Yes, but I'll need a little time to prepare."
Raynare reacted immediately to Issei's demand. Since she had once plotted to secretly steal a Sacred Gear without even informing the higher-ups of the Fallen Angels, she was quite familiar with illegal matters. Normally, one could only enter through a specific space under the underworld's management, but Raynare created a gate to a secret space without any long preparation. Then—
"That's it?"
"Yes, but—"
"Good. Come with me."
"Eh!? I have to go too? No! A disgusting place like that!"
"Huh? If I go alone, how am I supposed to come back!?"
"But..."
"Come with me while I'm still being nice..."
"O-okay..."
After threatening her with the [Rinnegan], he finally got her to come along, and Issei, setting foot in the underworld for the first time, said—
".....This is kind of different from what I expected..."
He had expected a hellish atmosphere with flames raging everywhere, but aside from the moon being red, it was no different from the human world.
"Of course. Even if it's the underworld, it's still a place where people live."
"Didn't you just say it was disgusting?"
"Of course. Just seeing devils swarming everywhere makes me want to throw up."
"Ah... so that's why..."
Still, to think you got into the underworld so easily. You're pretty impressive too."
"Well, yeah. I did aim to become an executive in the Fallen Angels, after all."
An executive of the Fallen Angels—once a dream, now in the past tense. After being caught by Issei, her sense of values had gradually changed, and now that kind of dream no longer meant anything to her.
"So why did you come to the underworld?"
"To do this."
Boom
As he said that and formed a hand sign, a cross, beside Issei appeared something strangely familiar in a cloud of smoke. Black hair that fell to his back, red eyes, and a man wearing red armor—the figure of the strongest Uchiha.