Sayuki Mukai (32), who works in the accounting department, has never had a romantic relationship and is thinking of living alone for the rest of her life, and is working hard at her job. Until now, Sayuki has been living at her parents' house and working hard to save money, but when her younger brother and his wife come to live with her, she starts living alone. Then, the person who lived next door to her was Kenta Miura (27), who was recording expenses full of defects almost every day. Sayuki gradually becomes attracted to Kenta, who she thought was her weak point, but due to Kenta's lack of self and shyness due to the age difference, her late first love becomes complicated... *Episodes 1 to 10 will be drawn by Nana Nanase, and from episodes 11 to 15 by Sashiro Sayo/Ayakami.