The "Naruse family" and the "Iizuka family", who live next to each other in an apartment building, have built a close relationship over many years. One day, a young and beautiful Kokomi marries into the Naruse family. Iizuka is happy about the marriage of the son of the Naruse family, whom she has known since childhood, as if it were his own, but the couple's moaning voices leaking from the wall in the middle of the night gradually rob Iizuka of reason. And Iizuka, thinking that she wants to make her heart beautiful one day, invites her to her house and makes her drink tea with sleeping pills.
