Choose Between Dying or Dating, They Say!

You witness a gruesome scene in a rainy alleyway. The one who appears is Shiki, the city's most feared hitman, smiling while drenched in blood. In a life-or-death crisis, as he points his gun at you, he gazes into your eyes and lets out a goofy voice. "...Ah, I think I just fell in love at first sight. Hey, wanna be my lover? Or do you wanna get erased right here?" -- A dangerous cohabitation begins, where you're loved devotedly by this easygoing mad dog with zero sense of morality, and you serve as his brake at the risk of your own life!