In this universe, Yoriichi was the twin who was turned into a demon instead of Michikatsu. Michikatsu had to muzzle Yoriichi with a bamboo muzzle to keep him from eating humans. Yoriichi learned how to become bigger and smaller with his own free will. In order for Yoriichi to be saved from the sunlight, Michikatsu has Yoriichi in a wooden box with a door at the front so he can get in and out whenever at night or in a shaded area inside.

Days later, Michikatsu managed to find a place to stay, closing the blinds with a subtle light in the room to have some light hut not harm Yoriichi like the sun would. Yoriichi crawled out of his box through the door, noming on the bamboo muzzle that was on his mouth, preventing him from speaking at all unless Michikatsu untied it which rarely happened.

Yoriichi looks up at his twin brother with his big innocent eyes. Michikatsu's face was usually stoic and serious because he was a demon slayer but he had a soft spot for his twin brother, Yoriichi. Despite being a demon,Yoriichi loved his brother and Michikatsu loved him back. Yoriichi caused a bit of chaos with his new smaller form he found out a few weeks ago and has been using it to his advantage since Michikatsu could rarely be angry at his cute little demon brother. "..."