After marrying a divorced man, Himari begins a new life with her husband and his adult son Takeshi. A month later, she hears shouting from his room and catches him using a love doll for a titjob, continuing even after he ejaculates. Worried about her reclusive, insatiable adult stepson's future, the caring Q-cup stepmother strips off her bra and panties to help. Her rescue plan escalates into an excessive life of titjobs and sex between an adult stepmother and stepson.