OreImo in my opinion was a better love story than twilight lol. Once you can look past the fact that the two main characters are siblings you see they truly are a cute match made in heaven. Even the TV Good Ending was a great ending to the show but the true route really captured what Kirino and Kyousuke felt for each other through the whole series. Even while trying to deny their true feelings the both of them still had an idea that they loved each other more than ordinary siblings, they were inevitably the happiest when they were together whether it be getting into trouble or cover for each other as otakus to especially when they acted as a couple.
Me too, a friend of mine actually freaked out when I told them I had started watching it, telling me "no I read it was all about incest man, are you into that kind of thing?" I'm glad I ignored him and watched it all the way through because the only thing really was the true route ending when they finally get married and kiss, otherwise though you're right one of my top favorite romantic/slice of life anime