Nighty Night, Dear is a story about a grumpy girl in her early twenties called Koko who suffers from insomnia as she collects and relives her embarrassing moments each day using a magical memory machine. One night, being jealous of other people having a good night's sleep, Koko decides to disturb a little boy's (Josh) sleep. She collects Josh's memories and makes him recall his own embarrassing moments, but things don't go according to her plan.