Title: Masturbation Addiction
Author: Yamata no Worochi
You can easily find it on the sadpanda.
Personal note: I have no way to check what I'm about to say, but I think he was probably one of the first to draw extreme gapes and prolapses, especially cervical ones, and he was probably the very first to draw a woman pulling her ovaries out of her prolapsed cervix. I dislike how he draws the genitals, but it's enjoyable nonetheless.