Sana's husband is married to a flat-chested wife, but he's obsessed with big breasts and has fallen head over heels for her busty friend, Satomi Shimizu. He secretly dreams of burying his face in those large breasts, devouring them hungrily, and somehow having sex with her. One day, his wife suggests hosting a home party—this is his chance! Determined not to let it slip away, he begins scheming to seduce her. When Satomi comes over to borrow a camera, claiming she wants to film her kid's sports day, he seizes the opportunity. Under the guise of teaching her the best way to improve her filming skills, he introduces her to the world of gonzo porn—by instructing her in hardcore, face-to-face sex filming.