Sosuke and Saeko met at the izakaya "Kitao" and are neighbors who have a delicate relationship, but they plan to get together Keiji and Marie. Today, they invited them to their house for drinks, but a drunk Sosuke starts to flirt with Saeko in the bedroom so that the two of them, who are on the other side of the wall, don't notice. Keiji and Marie, who have fallen asleep, notice the atmosphere...?!