Need help not having video show in SERP

Hello,

A website I run is having problem with having a pornographic video show in the SERP. The site has zero pornographic material on it and we have no idea where it came from.

We are afraid of going to google to have them take it town for fear they may de-index the site or discover our older link building pyramids.

Any way I can get this video from showing in the SERP?

Did you acquire the domain form someone? Maybe the video link was used by the previous owner of the domain name. I think if you have a Google Webmaster account, you can use the demotion feature to remove the video link or just add the link of the video to the robot.txt file on your website under the disallow list.

We've held this domain for almost a decade now, it's a trusted domain.

Wouldn't demoting hurt the link itself? (tld/x/) we want to have /x/ to keep ranking but we want the video image out of the serp.

As for the video link, we cannot find it. Google in the SERP says there's a video, when you click on it, it just sends you to the vanilla page.