His Sister Thinks He Wants to Have Sex With Her Fiance Even Though He’s Straight

This story is a little outside of our wheelhouse, but it was just too weird in a good way to pass up:

How do I (24M) convince my sister (31F) that I don’t want to f*ck her fiance (~30M)

I know the title sounds strange. I’ll try to be concise with all of the context. I [24m] have a sister [31F], and due to the age gap, we were never close. We grew up in the US, but after college, my sister moved to Europe. I haven’t seen her much since she was 18 (and I was ~11), but because we weren’t very close, we were fine with the occasional texting and every-other-year Christmas visits.

Two very important pieces of context for this story. The first is that, even with the age gap, we look EXTREMELY alike. In the few times she’s been home since I was older (~16 and ~23) people have commented that we could be twins. The second is that I am 100% straight. I’ve only ever dated girls, and have never been interested or experimented with men in any way. I’ve been with the same girl since I was 21.

Ok, so onto the main story. About a year ago, my sister met her fiancé, who I’ll call Rob. I met Rob for the first time this Christmas. We quickly bonded over a shared hobby (Runescape, lol). We chatted a ton while he was here, and because it was Christmas, we were usually drinking. He seemed a little touchy (touching my arm / my back, laughing a lot, a few oddly-timed hugs). I thought nothing of it, maybe that’s just how Europeans are (I’ve never been).