Ch. 1-3: A popular second year guy rejects a girl who left him a love letter without looking up, only to find a very popular first year guy. The first year gets mad and kisses him and then proceeds to have sex with him. Afterwards he searches for his "Cinderella" from lunch by kissing people.
Ch.4-7: Story of the playboy school president who is the cousin of the first year in the first chapter. The president kisses a guy as a joke only to be knocked in the head with the guys briefcase. The guy mentions the popular model named "Kana" that the president slept with and the president has sex with him to keep him quiet. The president ends up falling for the guy and tries to find Kana because he assumes the guy is in love with him.
Ch. 7.5: Both couples trying to find spots in school they can have sex, but they keep bumping into each other.
Koishiteru!?