The story envolves around Kwon Tsurashi, Song Eri, Jung Fern and Kwon Momo, four girls in their 2nd and 3rd year of high school.

Song Eri, a 17 year old girl who's usually a really shy girl but can be really crazy at times, especially when she's with Key. They have been friends for as long as they can remember, childhood friends if you want to call it that. They're really close and have done pretty much everything together, they're pretty much inseparable. And skinship, that's as natrual as breathing. But maybe not anymore...