Lunn is a young adult who lives with his uncle, his grandad and two friends. They play, cook, and clean the house together, but they never leave it. He doesn't care about that, because as long as he is with his family he will be happy. Especially now that his birthday is approaching. His whole family will have a big party yayy!! Everyone will do their best to carry it out. However, a sixth person appeared in the house! He doesn't look aggressive, so they included him in the preparations. That event, and the old photo found by Lunn, put everything into perspective.
Who is the sixth person?
Why do they never leave the house?
And why does he start remembering something he shouldn't...?
Wait. What?