(Y/N) is a normal oni going about her days torturing sinners in Jigoku, that is, until King Enma approaches her with an odd request--seduce Hozuki, her childhood friend.
Riddle x reader
Important info:
{y/n} is used with they/them pronouns, but is mentioned to be afab. Transmasc and enby friendly. They also have a fantasy illness of some kind that can't be cured, which is why they're at NRC to study possible cures. Riddle and {y/n} hate each other at the beginning. {y/n} isn't yuu, but yuuka (the book 2 protagonist in the manga) is a character. I tried to leave as much as possible vague about the reader while making them more than a piece of cardboard.