C/o SF Weekly, please enjoy (or balk at) these NSFW photos from the 9th Annual Masturbate-a-thon which went down last Saturday at the Center for Sex and Culture.

Among the celebrity, um, judges, er, guests, was Sister Roma (link semi-NSFW) of the Sisters of Perpetual Indulgence, and among the competitors was record-holder and current world champion wanker, Masanobu Sato (pictured), who flew all the way from Japan to defend his title. He in fact bested himself, setting a new Men's time record of 9 hours and 58 minutes.

A new women's tag team record was set by several gals from cooperative strip club The Lusty Lady Theatre, and this dude, Jose Valdez, who shows up to show off (and masturbate) at each and every Folsom Street and Dore Alley Fair, clearly couldn't pass up a chance to jack off with the best of them.