MIDV-146 Nao Jinguji's cervix is developed with a large cock, leading to squirting, orgasmic pistoning, and a loss of control.

Nao Jinguji's erogenous zone, the portio, is developed slowly until it awakens, and she takes large AV actors' dicks deep into her uterus. The pleasure makes her body jump, and merciless pistoning leads to strong, continuous cumming, with squirting and over-orgasms that break her limits. She collapses into a state where reason and language fade, and she cannot return to normal sex.