Yuuya has liked kokoro since elementary school. recently they reunited by chance, and he confessed his feelings, and they started dating. yuuyas father is a teacher who was their homeroom teacher. yuuya brings kokoro home to introduce her to his father as his girlfriend. however, yuuyas father is fixated on kokoros large breasts. yuuyas father, claiming to have something to discuss about yuuya, invites kokoro over and, taking advantage of her trust in him as a former teacher, drugs her and forcefully pushes her down.