Minami, once an idolized teacher at a prestigious private girls' school, finds her life shattered when a male student makes physical advances during after-school tutoring. Another student witnesses the incident, leading to her expulsion for violating school rules. She is then threatened and assaulted by the vice principal and other staff. Deeply remorseful and deciding to step away from teaching, Minami faces a new crossroads in life. Gradually, she begins to mark her body with ink and descends into a sensual world of soapland work, covered in foam and serving clients. This story portrays her psychological transformation and difficult choices amid a harsh reality.