A British mother posed as a schoolgirl online to protect her daughter from a sex predator, collecting evidence that eventually landed the man on the sex offender registry.

The Teeside Crown Court released Matthew Jenart, 28, Tuesday after the judge said it was unclear what his intentions were with the supposed 11-year-old victim, despite writing he was looking for “naughty fun” in a chat transcript.

Described as an isolated loner by the defense, Jenart misidentified his age on Facebook by claiming to be a 15-year-old in school and friended the girl with a profile that included a fake photo.

The elaborate ruse was quickly stunted by the girl’s mother, who took over the Facebook account—which is apparently a growing parenting trend—after she grew concerned about her daughter’s communication with a stranger—especially when Jenart said he was just there looking for some “fun.”

What kind of fun? “Naughty” and “naked” fun, according to Prosecutor John Gillette.

In her online chat with Jenart, the mother claimed to be 11 years old. The man told her, “It’s only fun. Try it, you’ll like it,” and ended by writing “Cool, so you going to have fun?”

Jenart, an unemployed former hotel worker, was arrested in December for inciting a child to engage in sexual activity after the mother learned of his true identity.

Despite never coming in contact with the minor, Jenart received a three-year community order, was placed on a sex offender’s list for five years and was banned from working with children. He also received a lashing from the judge for his behavior.

“The chat you entered into in with [the girl’s] mother can only be described as disgusting when you consider you thought you were speaking to an 11-year-old and you were lying about your age,” the judge said.

After hearing the court’s announcement, she was disappointed that Jenart didn’t receive any prison time.

“I’m surprised the judge said he wasn’t sure of his intentions. I was the one on the receiving end of his messages and they seemed pretty clear to me,” she said.

“I felt physically sick exchanging messages with him. I kept coaxing him until he said he wanted ‘naked fun’ with my daughter, at that point I couldn’t go on any further and I called in the police.”

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