All fine that you think a kink is weird or don’t understand it. There are enough kinks out there that wouldn’t be appealing in the least to me as well. But as long as we are talking about an consensual act and no real harm is done, either communicate those thoughts in a respectful way or keep them to yourself.

Telling somebody it is fucked up that they enjoy or masturbate to something that is done consentually and that they are disgusting for it, is nothing more than kink-shaming. Calling it harassment might be a bit much, but that you received some backlash (if you’ll pardon the pun) seems to be warranted in this case.