Aimu Yuu (remark: his name sounds like "I'm you") is a high school student who just moved into Yaninari Sou, a cheap boarding house in Tokyo despite the rumor of this place being haunted by ghosts. Upon his arrival, he finds out that he's sharing room with a female ghost named Mii, who immediately takes a liking to him and insists on clinging to him till he dies. Not only that, but Yaninari Sou is filled with weirdos like Hinata Teruaki, an antisocial guy, Gouda Karuma, a 8-years ronin with luxuriant hair, Ogura An, a weird Shoujo Mangaka, Buraide Mari, a former pro wrestler, and last but not least, the mysterious landlord Ooya Oya who's always wearing an armor suit. The only normal person Yuu can find here is his classmate Ooya Ai, the landlord's daughter, and she also seems to take a liking to him, but will this be enough to help Yuu get through his high school life in peace? The title "Yuu & Mii" is a pun on the English phrase "You and Me". There are a lot of weird characters in this manga.