Recently, Hyaku Mika is addicted to Korean wave stars. - She regretted watching the DVD while she was sleeping, and Momika completely neglected her housework. - It was Hideki, her only son, who didn't complain even if she saw a room that was getting rough and a meal that was too simple in her life with her mother. - One day, when she returns home, she discovers an object that runs around her room endlessly. - She approached it and it was a robot vacuum. - Hideki laments, "Is my mother's omission so far?"