Male heartthrobs in movies based on shōjo manga (girls’ comics) generally share one attribute: They’re romantically unavailable to the frustrated female protagonist in the opening scenes — or even for much of the film.

The latter dynamic is at work in “My Love Story with Yamada-kun at Lv999,” Yuka Yasukawa’s sweet, leisurely paced romantic comedy based on a bestselling manga by the single-named artist Mashiro. The college student protagonist, Akane Kinoshita (Mizuki Yamashita) falls madly in love with Akito Yamada (Ryuto Sakuma), a high school student who is not only uninterested in romance (and tells her so to her face) but also emotionally blank with a vocabulary that doesn’t extend far beyond “yes” or “no.”

Nonetheless, at his elite high school Akito makes female classmates swoon just by walking through the halls. Seeing this comically staged spectacle, Akane starts to lose hope. Given this swarm of rivals, what chance does she really have?