Memories Off 2nd

Shirakawa Hotaru, a girl who's in love with Inami Ken, finally confesses her love. From there on, they were happy couples, until one summer. Ken met a new friend, Tobise Tomoe, who is Hotaru's best friend. Tomoe seems to have her own charm. Ken, now have two paths to choose from; to be with Shirakawa Hotaru or Tobise Tomoe. Otherwise, he will lose them both.

Synopsis from Anime News Network