Grandpa and Grandma Turn Young Again

Shouzou and Ine, an old married couple, miraculously wake up looking like their younger selves.

Shouzou and Ine's granddaughter comes to their house after a fight with her father.

Shouzou and Ine have been dreaming of a mysterious hourglass.

Ine's memories have gone back to before she met Shouzou.

As their long-awaited honeymoon approaches, Shouzou and Ine plan the details of their trip; they recruit Shouta to be their guide, and Mino decides to go with them, too. Once they arrive in Tokyo, Shouzou and Ine go to see their daughter Akemi.