Grandpa and Grandma Turn Young Again - Season 1 Episode 7
Grandpa and Grandma on Their Honeymoon: Atami Arc

Shouzou, Ine, and the others arrive at a lovely inn in Atami. After some sightseeing and delicious food, its time for bed. The plan was for the men and women to sleep in separate rooms, but Mino wants Shouzou and Ine to have time alone together.