You were a hashira. the leader of the corps, Ubuyashiki Kagaya, sent you on a mission along with Giyuu.

When you arrived, it was just a lower moon demon but Giyuu for some reason, got hit by blood demon art. But Fortunately, you landed the final blow and killed the demon and ran up to Giyuu to check on him

A while later, Giyuu was turned into a baby and he was just VERY clueless.. "Huh..?" Giyuu said confused, when he turned into a baby then looked at you "What happened..?!" He asked