Refrain Blue  

RB, リフレインブルー, Refrain Blue (リフレインブルー)

A beach excursion for two individuals grieving the loss of their loved ones turns out to be more than anticipated. Perhaps, an enigmatic female known as "Umi Warabe" can aid them in healing their wounds and progressing with their lives. Matsunaga Yoshihiro serves as a chaperone for a group of high school students on a summer beach trip. During the night, he rescues one student, Morisawa Nao, from drowning herself. She had previously been on this same journey with her fiancé, who tragically perished in a plane crash a year ago. As these two individuals develop a relationship, it is revealed that Yoshihiro also harbors a painful secret from his past. Watching over everything is an enigmatic young girl who seems to be present at crucial moments.