Yotsunoha
Japanese title: よつのは
Type: OVA
Episodes: 2
Source: Visual novel
Genres: Romance
Studios: HAL Film Maker
Producers: Rondo Robe, Geneon Entertainment
Duration: 36 min per ep
Rating: PG-13 - Teens 13 or older

Based on the game by Haikuo-Soft.

A story about the reunion of 4 childhood friends, Yuzuki, Matsuri, Nono and Makoto, in their deserted old school campus, Mochitsuki Academy. 3 years ago, they buried a time capsule under a tree inside the school and made a promise. A promise to meet again after exactly 3 years from that day. And the day of promise has finally arrived.

(Source: AniDB)