Fune wo Ukaberu

Tsuji Chiaki's high school life hasn't had much ups and downs, but it's not bad either.
Until a naive, sheltered boy, Yamaji, intrudes into his life.
He is a jealous guy who gets very possessive about Tsuji,
Chiaki finds him troublesome and a little bit weird.......?

Note: The chapter count includes the side story "Baka Datta nda".