Tsubaki, after marriage, gradually becomes infatuated with her stepdaughter Nono Akari. Nono, having been raised solely by Tsubaki since her father remarried, is drawn to his warmth and kindness. Tsubaki, in turn, has long harbored feelings for Nono even before their marriage. Unable to resist, Nono falls deeper into this forbidden relationship, and the bond between the two grows ever stronger.