Ryou is a 17 year old guy whose parents separated a year after he was born and he has only once seen his father, Konomi, since then. However, his mother is dating a new guy and Ryou is feeling confused and just wants to see Konomi again. But when he visits his dad, something goes wrong and Ryou finds himself 22 years back in time and Konomi is 14 years old. Konomi does not know who Ryou is, and Ryou does not know how to deal with the situation he is in and his growing affections towards his father that have nothing familial about them.