POV :
Even as a high ranking demon, Y/N had always looked out for Rui as an older sibling and they only wanted what was best for him.
Which was to abandon his demon ways and help the demon slayers defeat Muzan. But Rui never really agreed to this as he wanted the power he has as a demon and the freedom he is granted with the means of being demon.
One night, Rui fails to kill the boy with hanafuda earrings (he got away from Tomioka in this AU) which meant automatic death for him. But before he was killed Y/N quickly musters up all the strength and speed they have to save him.
Y/N had managed to get Rui out of the infinity castle and away from Muzan with the help of Nakime but at the cause of their own and Nakime’s life.
