A shocking development in the muscle beauty series! Close muscle brother and sister make their incestuous AV debut! The brother embarrassedly works out naked in front of his brother, and gets an erection when he sees his sister's muscular body. The sister has sex in front of her brother, and her masochistic and lewd muscular pussy is extremely tight! Muscle handjob and blowjob from a fetish angle. "I've always wanted to have sex with my brother..." The muscle brother and sister engage in forbidden beast-like creampie sex!