Tide-Line Blue: Kyoudai

A trip to the beach turns out to be more than expected for two people who are mourning the losses of their beloved. Perhaps a mysterious girl known as the "Umi Warabe" can help them to heal their wounds and move on with their lives. Yoshihiro Matsunaga is the chaperone for a group of high-school students on a summer trip to the beach. One night he saves one of the students, Nao Morisawa, as she attempts to drown herself. She had been on this same trip a year ago, with her fiancee, who was later killed in a plane crash. As these two get to know each other, we find that Yoshihiro also has a painful secret from his past. Watching over everything is a mysterious young girl who somehow is always there at decisive moments.

No synopsis available.

OVAs included with each Eiyuu Kyoushitsu Blu-ray volume.

Five years ago, something horrifying happened on Kamioki Island. Something so nightmarish that it stripped all memory from Mari Wakatake's mind even as it left every other human on the island dead in its wake! Now enrolled against her will at an isolated girl's academy, Mari is unaware that hidden eyes are watching her, waiting for her memory to return. Buried in her psyche is the most terrifying secret of all: while Mari was the only human who lived, she may not have been the only survivor! As something in a female skin invades Kaihou Academy, Mari's only hope may lie in a strange girl to whom she is inexplicably drawn yet cannot trust.