Funny you asking something like that, one of my greatest friend who i didnt talk for 6 years well we got back together, as friend ofc she told me we were like brothers she told me secrets, i pretty know all of her intimate secrets, that didnt stopped us from having some good time

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What work for me was always teasing her, never taking me so serious, alot of kino, dont be afraid to grab her. telling her all of my sucess with women, and asking for opinion she became jealous and start noticing me as man. And more important if she told me we were like brothers then im going to treat her like my little sister if you know what I mean. belive me drove her mad, then she start asking me for compliments ofc i tease her to death, to a point she tells me if she is not good enough for me

. Hot girls dont like being rejected.
But if you are going to be the "gay friend" that does everthing for her being the nice guy giving her compliments, and afraid of kino with your sister guess you wont go far
But I have to say i was suprised when we made out.