Gyakusou Shoujo: Owaranai Natsuyasumi

Toko is a shy, awkward girl who hates her summer holidays. They just don't seem to end, and she's right. She is stuck on August 31st. Every day's the same as any other August 31st, except when a new character comes and changes how her whole day goes, and what she learns later on is not what she wanted to know...