Jake Waton won over teenage girls on social media, swapping flirty messages and intimate pictures with them online before meeting them in person. For many of them, the 16-year-old was the first boy they dated.

But Jake Waton was actually Gemma Watts — an adult woman. The British 21-year-old posed as a teen boy to groom and sexually assault girls as young as 13, wearing baggy clothing and tucking her long hair under a hat to fool her targets and, in some cases, even their parents.

On Friday, London’s Metropolitan Police announced that Watts had been sentenced to eight years behind bars for incidents involving four girls. She pleaded guilty to seven sexual assault and grooming charges for crimes that Judge Susan Evans said caused “severe psychological harm” to victims.

“Their age, as you plainly knew, made it more likely that they would be sexually naive, enabling you to get away with your deception,” Evans said during sentencing, according to the Independent.

In what police described as “a bizarre and elaborate web of deception,” Watts created profiles for “Jake Waton” on Facebook, Instagram, Snapchat and other platforms. She shared skateboarding videos, used teenage slang and claimed to work as a cashier at Hollister, a clothing store popular among teens. In photos, she gazed out from beneath a baseball cap or hoodie.

Posing as Waton, Watts liked photos shared by teenage girls and struck up relationships with them, calling them “babe” and other pet names in messages. She built their trust online and through phone calls, police said, before arranging to meet. She traveled across the U.K. to see them.

Authorities said they began investigating in April 2018, after a 14-year-old girl reported being sexually assaulted by her boyfriend, whom she identified as Jake Waton. Police discovered Watts’s true identity and two additional victims, both under 18.

They arrested her in July 2018. Under questioning, police said, she admitted to grooming victims while pretending to be Waton and to committing some of the assaults.

“I was only trying to cheer them up,” she claimed, according to The Guardian.

As the investigation continued, Watts was released on bail. Then, in October 2018, she was found with a 15-year-old girl whose parents had reported her missing. The teenager told police she too had been sexually assaulted by Watts, who was arrested and taken into custody again.

She was charged in September 2019 and pleaded guilty two months later. Metropolitan Police Detective Phillipa Kenwright told British media outlets that authorities believe the extent of her crimes may not yet be known, telling the Independent, “I think there will be further victims, who were in a relationship with Watts, who will now realize she is a woman."

Defending Watts in court, Patrick Maggs said his client understood her crime was serious, the Independent reported. But he pointed to her low IQ, lack of maturity and struggle to accept her sexuality as mitigating factors.

“With Gemma Watts’s low IQ, with her immaturity, I would invite the court that that represents that she was almost certainly going to be trying to socialize with those who were younger than herself,” he said. “Whatever else it was to present as a boy was indicative of Gemma Watts’s entire failing to cope with her own sexuality.”

The judge acknowledged those factors during the sentencing hearing, but also noted the harm Watts had caused.

One 14-year-old girl said in a victim impact statement that her “heart exploded” when she learned the truth about Watts from police.

“My world stopped, I actually stopped breathing. … I loved him so much,” she said, according to the BBC.

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