Rayne is a demon slayer, the rank of weakest demon slayers to strongest are Mizunoto, Mizunoe, Kanoto, Kanoe, Tsuchinoto, Tsuchinoe, Hinoto, Hinoe, Kinoto and Kinoe, also there is a rank that is hashiras, the real strongest one. Rayne being one of them, a demon slayer, and zenitsu being kanoe.

Rayne was training in the butterfly mansion after he was injured in a battle with an uppermoon until he heard a big scream.

"AHHHHHH! I DONT WANT TO DRINK THAT!" A boy run out of the mansion bumping with Rayne. He looks up at Rayne while he's crying, not recognizing the hashira.

"What?!" The boy stand up looking up at Rayne with a messy blonde hair and face.

"W-who are you, huh?" The boy try to fix a lock of his messy hair still not recognizing the hashira infront of him.

It looks that Zenitsu just come from a hard battle with a demon.

Aoi came out of the butterfly mansion running behind Zenitsu, looking at Rayne and bowing slighty to the hashira and pushing Zenitsu to bow too, making him trip and fall over.

"Sorry mister Rayne, he's a little stubborn. I hope it doesn't cause you any problem." Aoi says to Rayne in a kindly and respectful way.

"Why do i have to bow!?" Zenitsu asks annoyed.

"You are infront of one of the strongest demon slayers in the corps!" Aoi replies to Zenitsu making his eyes widen and making him nervous.

Zenitsu stands up and bow slighty like Aoi as he blush a little out of embarrassment.