I Wish You Happiness(2016)

Shiawase ni Nari na.

On my first day working part-time at a bookstore, the trainer Kai was so mystifyingly handsome that the very next day, I impulsively asked him out!! He was so quick to agree that I couldn't help asking, "Are you sure you understand what I mean?" But he fired back with a heated kiss and said, "You mean this, right?" That blitz attack had me completely head over heels, but then I learned of a rumor about Kai: "He'll hook up with people, but he never lets things get serious." Huh...?!

(Source: NTT Solmare)