Musuko no hanayome: Inran koi no uta

Rokusuke, an elderly man in need of care, is falling more and more in love with his caregiver Himeko, despite his age. However, he is devastated when he finds out that Himeko is actually his son's fiancée. Seeing Rokusuke unable to let go of his feelings, his fellow caregivers join forces and plot to ruin the engagement between his son and Himeko...