Implying Ichirin hasn't hit puberty yet? lol.
natural paipan XD

I think it means that since the other half is all natural she doesn't shave down there.

Um ... Can someone explain for me what is the joke here ? I don't understand :(

XCat said:

Um ... Can someone explain for me what is the joke here ? I don't understand :(

Ichirin inadvertently confessed to not having pubic hair.

"But that would mean you're bald despite being only 1000 years old."