Natsu-iro no Sunadokei
English title: Sandglass of Summer Colors
Japanese title: 夏色の砂時計
Type: OVA
Episodes: 2
Source: Visual novel
Genres: Drama, Romance, Sci-Fi
Studios: Picture Magic, Rikuentai
Producers: KSS
Duration: 30 min per ep
Rating: PG-13 - Teens 13 or older

Makimura Koutarou has made up his mind: during the summer vacation, he is going to confess his love to the seemingly unapproachable Serizawa Kaho. Yet, on the night before, he has a run-in with a strange girl - an encounter which propels him into the future. There, he learns that not only has Kaho-chan become his girlfriend, but she has also died in a tragic accident. Returning to his own time, Koutarou sets out to change the future and save his love.

(Source: ANN)