Viewers of the ITV2 reality series were shocked when she shared a kiss with new girl Katie Salmon, following their date during last night's (3 July) episode.
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Katie and Sophie enjoyed a cosy date on 'Love Island'
ITV
However, there was no-one more stunned than Tom, who could only watch on at home as his girlfriend kissed another woman.
Taking to Twitter as the show aired, he made his feelings on the matter very clear:
Tom had been in an on-off relationship with Sophie before his elimination from 'Love Island' last week, and since his exit, he's insisted they could make it work on the outside, despite their ups and downs in the villa.
She said in the Beach Hut: “She has said that I’m her type, but I’d like to get to know her before I start jumping into things. Like I say, it’s early days with her and Tom. Obviously I might have limited time in here, so I have to move quite quickly. But you can’t move too quickly because you can’t look too desperate, so you’ve got to play it cool.”
'Love Island' continues tonight at 9pm on ITV2.
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'Love Island' Contestants 2016
The 2016 'Love Islanders'(01 of12)
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Scott Thomas(02 of12)
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Scott, 27, is an entrepreneur and club promoter from Manchester and has been single for six years. He is the brother of 'Coronation Street' star Ryan (Jason Grimshaw), and 'Emmerdale' star Adam (Adam Barton). He says: "They support me, but I want to do this on my own. I've been brought up with it so I'm prepared in a way, but it's my turn now. It doesn't scare me, that side of things." (credit:ITV)
Cara De La Hoyde(03 of12)
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Cara, 25, is an international circus performer from Kent and has been single for ten months.She says: "I was on 'First Dates' a couple of years ago. He paid for the dinner which was alright, but he loved himself." (credit:ITV)
Daniel Lukakis(04 of12)
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Daniel, 23, trained as an osteopath and physiotherapist and is now a model. He’s from London and has been single for a year. He says: "I was scouted by David Gandy. I was in the gym, and saw him, and I'd followed his career for a very long time so we had a chat and he put me in touch with his agent, who signed me." (credit:ITV)
Sophie Gradon(05 of12)
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Sophie, 30, is a marketing manager from Newcastle and has been single for seven months. She says: "I used to date Danny Cipriani. Suddenly I was in the papers being called a 'Kelly Brook lookalike', which is nice, as she's stunning!" (credit:ITV)
Javi Shephard(06 of12)
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Javi, 27, is a Surveyor from York and has been single for seven months.He says: "She has to be perfect! She has to be intelligent, athletic and healthy, and just have something about her. She should just be fun. I want a girl with good energy, who makes me happy." (credit:ITV)
Zara Holland(07 of12)
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Zara, 20, is the current Miss Great Britain. She’s from Hull and has been single for two years. She says: "I do like tall, dark and handsome. I like a guy to have nice dress sense. I'd love it if he turned up in a blazer and a baby blue shirt! Not that I'm being picky or anything…" (credit:ITV)
Nathan Massey(08 of12)
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Nathan, 24, is a carpenter from Essex and has been single for seven months. He says: "I knock around with a few of the TOWIE lot - Tommy Mallett's one of my best mates." (credit:ITV)
Malin Andersson(09 of12)
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Malin, 23, is a make up artist from Bedford and has been single for two months.She says: "I was on 'Take Me Out' about four years ago, but I didn't get a date. I think I was too fussy. I kept turning my light off!" (credit:ITV)
Rykard Jenkins(10 of12)
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Rykard, 25, is a personal trainer from Kent and has been single for five months. He says: "I hate it when all girls talk about is how many followers they've got on Twitter. Life's about so much more than that." (credit:ITV)
Olivia Buckland(11 of12)
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Olivia, 22, is a sales executive from Essex and has been single for eight months. She says: "I like a guy with tattoos, messy hair, and muscles. And I like a guy with confidence." (credit:ITV)
Tom Powell(12 of12)
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Tom, 24, is a barman and fitness instructor from Wales and has been single since Christmas.He says: "I talk to my granddad about my love life. He's my hero. He taught me everything he knows. He's with my nan and they're very happy, so he must be doing something right." (credit:ITV)