This is a manga I've read quite awhile ago... 5d4k5w

The protagonist is a man in perhaps his early twenties, who confined himself to the basement. He's trying to punish himself for something, I believe. His necessities are taken care of by a butler-sort of person.

There was a fire in the story. I'm not sure whether he refused to leave the basement, or left it in order to save someone.

He's a genius of some sort, or really good at what he does. Maybe he's a detective? He write stuff (math equations? I can't ) on his wall each time there's a "case", and white-washes his walls each time the case is closed.

The art style was a bit old-school, if I correctly.

Does this ring a bell for anybody? 😀

I think it's Remote
Strange, once I forgot this manga too and ask in this forum... 😀

Yup, that it! Thank you, p3pelpe~

Ah, that girl. Now I know why it's not on any of my lists... 🤣