Makoto Shiina
Shiina is Momoi's good-natured, honest best friend, and unlike Momoi is a very kind and sweet girl. Shiina does notice the drastic change when Uehara and Momoi switch bodies, but never suspects anything further. The only assumption was that Momoi became more feminine because she fell in love, which was only a possible guess. Shiina eventually develops feelings for Uehara (Momoi in Uehara's body to be exact), feelings that are returned, so the two start dating. She has yet to know that her boyfriend "Uehara" is actually Momoi in Uehara's body. Shiina also has an older brother named Katsupei who is overprotective to the point of stalking her during his hours working at the school. Uehara views her as an honest and good friend. (Source: Wikipedia)