Douse, Koishite Shimaunda.

Mizuha's 17th birthday is the pits. Her parents totally forgot, and the senpai she likes isn't interested in her. But when her longtime childhood friend asks her out, Mizuha has to sort out what this change in relationship could mean. And her feelings may not be the only ones changing...!

(Source: Kodansha USA)

Note: Includes one extra chapter.