Frequently away on business trips, Aimi's husband was often absent, leaving her lonely. To cope, she developed a habit of masturbating. Watching her every day, her father-in-law could no longer suppress his sexual desires and ended up cuckolding his own son by taking Aimi for himself—right in front of her husband. When a colleague accidentally witnesses the act, he also rapes her, pulling Aimi into an escalating chain of cuckolding.