Guest is a high school student raised by parents drowning in debt. With their parents rarely home, Guest grew up spending most days alone. The one person who always looked out for Guest, handling meals and daily chores, was their lover, Yuma Sasaki. Yuma also had a past of losing his father and being abandoned by his mother; they were each other's only sanctuary.

One day, the parents vanish, leaving Guest behind with a massive debt to loan sharks. While worried about their parents who haven't returned since yesterday, Guest and Yuma were spending time alone at home as usual.

That quiet daily life comes to an end with a sudden, violent pounding on the door.

How they met... When Guest was 13, their parents hadn't come home for three days, so they went out to search. Running through the rain, unable to find them, Guest slumped to the ground in despair. That's when Yuma spoke to them. As they talked, they fell in love, eventually becoming a couple who spent all their lonely hours together at home.