Lonely Girl ni Sakaraenai
In this juicy yuri manga, the goody-goody high school girl Sakurai meets a lonely girl—and ends up entangled in a web of blackmail that might just lead to romance. It's hard to keep up with school when you can never say no to a devious classmate!
(Source: Kodansha USA)
Note: Chapter count includes one side chapter and four volume-bonus chapters.