His job was to delete content that did not depict or discuss child pornography.

A Kentucky man was sentenced Tuesday to 20 years in prison for being the global moderator of Playpen, the infamous darknet, child porn site.
David Lynn Browning, 47, was also ordered to serve a lifetime of post-prison supervision. This is punishment for his role as moderator of the Tor-hidden site. As moderator, he made sure that Playpen contained nothing but child porn and discussions of it.

According to the government, Browning

... was heavily involved in the day-to-day operations of the website—including managing membership, developing and enforcing strict rules and deleting website content that did not depict or discuss child pornography. Browning also admitted to spending hundreds of hours logged in to the website—authoring more than 1,000 postings, and designing the website logo.

The FBI seized the site's server in North Carolina in February, 2015. The bureau then ran the site and used malware for two additional weeks to monitor its users. The government said 51 people connected to the site have been prosecuted. However, in some instances, the government has dropped prosecutions rather than disclose the malware source code it used to discover the true IP addresses of Playpen users.

Another key Playpen player is 57-year-old Steven Chase of Florida. Chase, the site's former co-admin, is expected to be sentenced later this year. The other co-admin is a 46-year-old from Indiana named Michael Fluckiger. He was sentenced to 20 years in prison two weeks ago.
According to Browning's plea agreement, Playpen hosted 215,000 user accounts and distributed 50,000 images and videos of child pornography before the site was taken down.