It's been ten years since Sirius Black saw his younger sister (brother), so when James kisses him, he feels guilty. Only, there is a limit as to how much you can feel guilty, while simultaneously kissing the man of your dreams. Or: James meets a transitioned Regulus, and immediately falls in love, even though he doesn't realise it at first. Meanwhile, Sirius and Remus both start feeling "different" about eachother.
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