My Stepsister Is a Bitch!

The story follows high school student protagonist Kota, who suddenly gains a stepsister, Yuka, after his father's remarriage. Yuka appears pure and cute on the outside but is actually a cunning slut. She uses various tactics to seduce Kota, escalating from initial flirtatious teasing to intense physical relations, drawing them into a taboo sibling romance. Yuka's slutty nature gradually reveals itself as she engages in affairs with multiple boys at school and deliberately flaunts them in front of Kota, igniting his jealousy and possessiveness. Through a series of climactic scenes, the film depicts the eruption of adolescent hormones, the breakdown of family ethics, and the twisted love and lust between stepsiblings, culminating in a fierce family confrontation that explores the hidden desires in modern stepfamilies.