Gishin rankô: Yamiyo ni ugomeku mesu shiri

疑心乱交 闇夜にうごめく雌尻

Also known as 柔らかい檻, Yawarakai ori, Suspicious Orgy Female Butt Wriggling in the Dark Night

Four men and women who have never met before are brought together by a man in charge of an underground business. It was supposed to be a simple job, but someone's betrayal puts their lives in danger. Fleeing their pursuers and hiding in a house in the countryside, they become suspicious of each other as they try to figure out who the traitor is. Furthermore, the female caretaker they kidnapped also begins to behave in a mysterious way...