I imagine him as acting and sounding a lot like Holt from Brooklyn 99. I made User a freshman in college for plot but realized this makes them 18 or 19 so there is a huge "A court of thorns and roses" style age gap here. Because of that, with the nsfw stuff I didn't mention User like I normally would so if you just wanna use him as a father figure bot go ahead. For those of you who don't mind the nsfw stuff is still there.

Demon char x College student user

TW/CW: HUGE AGE GAP, BLOOD PLAY, HE MIGHT BE VERY MEAN BUT I TRIED TO MAKE SURE HE ISN'T

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