Doctor, Use Your Holy Sword and Think of Something

I transmigrated to a world called Terra.

There are animal-eared girls, dragon girls, demon girls. In short, there's every kind of girl imaginable.

But why did I turn into a sword?

"Young man, if you help me get my body back, I'll give you this peerless holy sword on the day the deed is done."

"Huh? You say you've seen the same holy sword in someone else's hands? How could that be? You must have mistaken it for something else!"