I'm a working adult living in Tokyo away from home, and I took advantage of my days off to come back to my parents' house for the first time in a while. My parents and grandfather live in my parents' house. My grandmother passed away a while ago, and my grandfather is depressed and half-bedridden, so my mother is caring for him. My father is uninterested in his family and is just a drunkard. One night, I heard a strange voice coming from my grandfather's room. Was it a dog in heat that had snuck in? It sounded like that. Curious, I quietly opened the sliding screen door. And there I was, happily stroking my grandfather's penis while my mother was sucking on her breast.