Aizawa has lived in the same apartment building for 6 years. Most of the neighbors are nice, but he has always had bad luck with the neighbors next door, who are noisy and annoying. He was happy when the annoying neighbor moved in a month ago, but was irritated when he saw that someone else was moving into that apartment. One day he found a package with his address but someone else's name, so he went to deliver it to the new neighbor and complain about putting the apartment number wrong.