We don’t know who painted this promo poster but we think it’s pretty nice. Looking around the internet we noticed that no good scans of it existed. Until now. Our pleasure. The poster was made for the roman porno flick Dan Oniroku ikenie shimai, aka Sisters To Be Sacrificed, which was based on a book by award winning erotic author Oniroku Dan and starred Minako Ogawa and Miyuki Matsumoto. The two play siblings who inherit their grandfather’s inn but are held captive and tortured by the employees. Conveniently, the place has a torture pit underneath with—among other diabolical devices—a seesaw with dildos attached that… Well, just have a gander below. Dan Oniroku ikenie shimai premiered in Japan today in 1987.
Based on length I'd say we've been trapped down here at least three weeks.