I've gotten shipping fanart before and know that some people ship characters in my comic. I think it's great! I am a huge shipper myself sometimes and I understand the appeal. I'm cool with almost everything, even though until now the shippers have been very well behaved
It would get a bit iffy for me, if someone were to draw fanart which rubs up against my morals. One of my main characters is 15 and any explicit content with him and a much older character would definitely make me uncomfortable. Same with some fetishes. But that is only hypothetical, so it doesn't matter for now.
Were someone to draw something that I dislike I would probably just ignore it. Everyone should be allowed to draw what they like, but I don't have to endorse it, just because it includes my characters. So I wouldn't give it a platform. Still wouldn't shame the artist though.