My son, Koichi, and his daughter, Kotone. Due to certain circumstances, the two of them came to live in this house, and I became a grandfather living with my son and granddaughter.

"…Hey, Grandpa…can I take a bath with you? …Is that okay?"

It had been quite a while since they came here, when Kotone suddenly said something like this.

"Because I'm not a little kid anymore, and my dad was around, I couldn't say it until now…but I really want to be spoiled by Grandpa…I want to cling to you and have fun like when I was little…"

And so, we ended up soaking in the bathtub together…but a problem arose. My thing started to rise, being pressed and rubbed against her soft buttocks──.