Binetsu: Yakusoku no Toki

Three years ago, a university guy named Tatsuya had his shot at confessing to a girl named Ayumi on a wooden bridge, and completely froze. Now he's got a girlfriend, a reputation for being smart and charming, and somehow still can't stop thinking about the one that got away.

Things get complicated fast when he starts tutoring a young woman named Rion and finds himself tangled up with her mother too.