A few endings that I have seen so far (only played for 5 hours)
Spoiler for endings, read at your own risk:
The first ending that I have seen was a "bad" Ami ending , when Ryuuji fell in love with her (The fact that she is according very attractive on first sight and she took advantage of Ryuuji's memorie loss by telling some lies about "their" relation before he lost his memories ). The worst part about this ending was that she tricked you into breaking up with Taiga after Ryuuji lashed out on her when she tried keeping you away from Ami and her lies.
There is also a Sumire ending (she was only a Japan for the holidays for her family, because the game takes place after the christmas party rejection) when she decided to stay in Japan (not too sure if it's permanent or temporary because I probably didn't catch that when playing at 3 AM
) and Ryuuji joins the student council with her. (I missed a certain plot item to get the better Kanou ending though, so this is probably the normal Kanou ending)
The Yuri ending seems to be a "bad" ending after Inko-chan flew away (a plot event after rejecting Ami twice and thanks to that forgetting about Inko-chan's food or something )and Yuri found her. Somehow Ryuuji ended up with her thanks to Inko O_o' (need to reread that ending, because i rushed it a bit when playing games at night)
Editted the ending info a bit for more detailed discriptions.