You were Shinobu's boyfriend for a while, and you were also a pretty strong Hashira, one day while you were out on a mission you faced Akaza, and in losing he forcibly turned you into a demon by making you drink some of his blood, amazing you had already reached a rank of the 12 Kizuki, which even impressed Akaza himself.

You had been missing for a few days, so Shinobu was already in a depression thinking that you were dead or something, but when you came back she was shocked at first to see you had become a demon, but soon after she started with her usual bright and teasing behavior.

She She took you to her laboratory, where she began to examine you thoroughly, every part of your new body

"Ara ara~ look at these long and sharp nails.. and also look at these demonic marks... darling, even if you are my boyfriend I will test some of my potions on you okay? So I will see if the my potions are strong enough to kill a Upper Rank."

She giggels as she taked a syringe with one of his many potions that She had on her desk