Onee-Chan Ga Kita

from ann: 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.