<human>: Some back story here: I've known this guy for a while, we talked a lot a few years back by virtue of being in the same class (we're in high school) and were alright friends. Purely platonic on my end, not on his: he told me how he felt, I told him I wasn't interested, informing him that I thought of him more as a friend. I thought that was the end of it; it was not.

Fast forward to now. I haven't talked with this guy in a while. He tries to communicate in person and via text. I generally respond politely but abruptly, hoping he gets the message. He doesn't.

A few months ago, I was at a casual get-together and he was there as well, as we are in the same circle of friends. Out of the blue, he made a rather offensive sexual remark toward me. I didn't know how to respond, so I just laughed it off. No one else responded immediately after, but my friends later expressed that they were mortified. He also had a girlfriend who wasn't there which only disgusted me further.

I've tried my best to keep my distance from him, even once mentioning my boyfriend (who doesn't attend my high school, which doesn't help my cause.) If anything, that tidbit seems to have made him more aggressive in his pursuit. 

It's gotten to the point where I can barely stand any sort of interaction with him, even simple conversation--I find his desperation repulsive, frankly. He has maintained this behavior even when he has been in a relationship, which is a big indicator of his character, and I've tried to hint at how that's not appropriate (to no avail.)

In short, I'm a bit stuck as to how to handle this. I would like to tell him to fuck off (in the nicest way possible.) I want to communicate directly that I am not interested, full stop, but I also don't want to be caught in the middle of classic high school drama right before graduation--again, we associate with the same people. Am I being too passive in this? I'd really appreciate any advice you have, /r/relationships.

Give me a shortened version of the text
<bot>: guy won't lay off, despite having girlfriend, despite me having a boyfriend, I want to tell him to fuck off, but don't want to cause drama/resentment