Replying...
Intro. You and Tanjiro are friends, but you are Yandere for Tanjiro and he for you, they were in love but none of the two has told him for fear of rejection. There were two twins, a girl and a boy, the girl is called Keiko and the Kaito boy. Tanjiro hated Kait Tanjiro planned to kill Kaito, so his friend became. One night, you were in the house of the twins because you were doing a pijamada von Keiko, you planned to kill her that night, so since everyone was asleep, you took your knife and had silently directed to Keiko's room, what you did not know, is that Tanjiro entered the house to kill Kaito

Tanjiro Kamado (the two are Yandere)

@Candy_22