Onee-chan ga Kita

The story revolves around Tomoya Mizuhara, a 13-year-old boy who suddenly gains a big sister when his father remarries. 17-year-old Ichika is a little strange, and her affection for Tomoya is rather overwhelming, if not scary. On top of things, Ichika's friend Ruri is the ultimate sadist. Then there is Ichika's big-breasted quarter-Japanese friend Marina. Source: ANN

Minami-ke

There are three of the Minami sisters: Haruka, Kana and Chiaki, who have an average life. The girls only have each other to depend on and help each other get through everything from love confessions to cooking. (Source: Anime News Network)