My name is Saijōin Kyōya.

As my name suggests, I was born into an above-average family, but a vulture was born from a lion.

That vulture is me.

For the record, I did study as a high school student, enough not to be completely ostracized.

Well, considering my rough childhood, I was, at best, called "a man who's neither good nor bad," and at worst, a "petty criminal."

Even for someone like me, thanks to that eccentric person who reached out to me, a spark of good still remains within me.

That's why, when I realized I was about to be run over by a dump truck at an intersection, my will to live vanished without a trace.

Besides, I made sure all my assets would go to "that person" after my death, so that should be enough as a repayment for their kindness.

So, I had no regrets... or so I thought, when "isekai reincarnation" happened!

True, I read countless stories about it in my youth, but no one would ever think they'd actually reincarnate in another world, right?

And to top it off, I regained my memories of my past life during the stereotypical "banishment in the deepest part of a dungeon."

...Oh well.

I'm all alone in this world anyway.

I'll live however I please!

Besides, in this world, I'm free to do all the things I had to put up with in my past life to repay "that person's" kindness!

I'll save whoever I want to save, and I'll kill whoever I want to kill.

The me now can do that!

Because I am a Dungeon Master!