Either contact an admin or, if you feel up to it, try to talk to the person doing this to you. Tell them that the joke is not funny anymore/never was in the first place. You shouldn't have to feel uncomfortable about playing the server because someone might give you sexual orders that are specifically towards you.
If you feel too uncomfortable to tell the person saying this stuff in private, tell an admin that you know first. I can definitely see that it's a bit hard to tell (from a person not in the situations standpoint) if someone is taking something as a joke or as harassment in a video game.
As for an admins perspective, if I was told this I'd try having a conversation with the person making said jokes and just say it's not funny to the person/not needed. If the person continues said jokes, tell a higher up about the situation and we'll be sure to handle it.
If you have any further questions, don't be shy to contact me or anyone else in the higher up staff.
Sorry, if this has already been answered for I've not had the time to throughly read this thread.
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