Seventeen Syrups

A dizzyingly sweet urge he is feeling for the first time. Kentaro, a second-year high school boy, meets Mizuki, a popular senior on campus. One day, Kentaro sees Mizuki with a girl in the infirmary, Kentaro catches Mizuki afterwards and impulsively kisses him....... A possessive junior x a playboy senior!

(Source: Shinshokan, translated)