Sakuramiya Shimai no Netorare Kiroku - Season 1

Saya and Hinata Sakuramiya, stepsisters who entered into a romantic relationship following their parents' marriage, have their secret discovered by Tachikawa, a member of the photography club. He uses this knowledge to blackmail them. The coercion begins with Hinata, whom Tachikawa forces into intercourse, documenting the act on video. When Saya visits the clubroom out of concern for her sister, she too is drawn into the situation. Both sisters are subjected to non-consensual sex and are ejaculated upon. This incident initiates a period of daily exploitation by Tachikawa. His demands progressively intensify, leading to the sisters being violated not only by him but by multiple other individuals as well.