Roblox, an online platform aimed at kids that allows for the creation of games by its users, can potentially be a hotbed of adult material and sexual situations.

The issue is over something called “condo games,” which can have simulated sex acts and nudity.

“Condo videos are basically, um, they’re like the dark side of Roblox,” 19-year-old user Dylan Lemus-Olson told CBS News.

These are games that pass the platform’s child safety features and contain nude characters who can simulate sex acts. Lemus-Olson has a YouTube channel where he goes by the screenname Dazzely, and he has more than 50,000 subscribers. On August 3, he uploaded a video called “no more condo videos… youtube’s gonna ban me lol.”

Other users have also noticed the trend. Fast Company’s Burt Helm told CBS that he was looking into condo games for a while, saying that they were like a party “where the parents are out of town.”

“Roblox has made a world where kids can build whatever they want, and with condo games, what they want is to be much more grown-up than I think anyone imagines they would try,” he said. “But the most shocking thing is that you see characters that are naked, and you see that kids have coded ways for these characters to have sex.”

A source at Roblox said they were aware of the condo game issue, and the company uses its moderation protocols to fight bad actors of all kinds. They have 1,600 humans moderating as well.

“We conduct a safety review of all images, audio, and video files through a combination of human review and machine detection prior to them becoming available on our platform,” CEO David Baszucki said in a blog post.

The bad actors are a very small group, the source said, and they want to subvert the system. A lot of them use third-party platforms, like Discord, to coordinate their efforts.

Roblox declined a CBS request for an on-camera interview and said that the company has “no tolerance for inappropriate content or behavior” and “a stringent safety system in place,” which monitors all content and acts rapidly when inappropriate content surfaces.

Another regular Roblox game called “Adopt Me!” was reported by Deranda Bordelon, the mother of an 8-year-old daughter. She said someone in the game took her character and simulated a sex act.

“All of a sudden, she brought me to this other room and took her clothes off and was asking me to take my clothes off and just all kind of, you know, adult stuff that shouldn’t be for kids,” she said.

The game has also had issues with hackers stealing login info in the past.