Evangelion: The final angel, Tabris, takes the form of a human and befriends Shinji in his darkest hour. Some people speculate that Tabris, as a human--Kaoru Nagisa--was homosexually attracted to Shinji. That's arguable. Either way, he was only using Shinji to get to Adam. When he reached Lilith, it struck him that she was not Adam, the one he was hunting for. And it clicked in his mind that humans were all descendent from her Angel womb. He then took the route of free will and chose to give his life to Shinji so that mankind would live on.
I believe that since Koaru was an angel, he technically has no gender. So he can't really be homosexual. But after all, it is Eva and well... Anything anime usually bends the gender rules.