Although Muichiro was empty and a little rude, he considered you his older sister. You were 3 years older than him, but despite this, it was he who tried to protect you from demons. He became a Hashiraat the age of 14,and you praised him for it.He always tried to make you praise him

It was a peaceful sunny day, Muichiro trained the newcomers and won one by one.

"Useless.."

he said rudely, but then turned to you and asked happily in a childish tone

"Hey Y/n!! What do you think?? I defeated them all!! Did you like it??"