If you live under a rock you may not have heard that the pop world's most adorable young couple have reunited. Well, maybe.

That's right, Selena Gomez and Justin Bieber might just be back together,according to these photos of them together and other compelling evidence.

But, why are the pair back on?

The now 25 year-old Gomez and 24 year-old Bieber first dated back in 2010.

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Theirs was a roller-coaster romance, and it ended abruptly with a stint at rehab for her and a DUI arrest for him. The pair have also been accusing each other of infidelity as recently as 2016.

Bieber has been attached to various women, whilst Gomez's love life was firmly with one leading man, Abel Tesfaye, a.k.a The Weeknd.

Selena Gomez and The Weeknd | ELLE UKpinterest
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Ten months of trips to Italy, cuddling and pet-shop browsing later, Gomez appears to have returned to the Biebs like a moth to the flame. But why, we ask ourselves. Why?

Well, a source apparently close to the pair has spoken to People saying that the 'Wolves' singer has always seen 'the best' in the 'What Do you mean?' crooner.

In fact, we can totally relate to why she has potentially let him back into her life. They were each other's fist loves, after all. The source says:

Justin was Selena's first love. He will always have a special place in her heart. She's always held out hope that one day the circumstances and timing would be right. There have been times in the past where Selena was excited and thought things would work out again, but then was disappointed {by how things turned out}.

As for Bieber, 'no one ever came close to comparing to Selena. He always thoughts she was the most special and now seems mature enough to realise Selena deserves the best.'

Selena Gomez | ELLE UKpinterest
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We could not agree more.

And whether they're serious or not? The source said: 'They're having a great time together. Neither are seeing anyone else and they seem happy to leave it at this for now. Spending time together makes them both very happy.'

If they are making each other happy, that's good enough for us.

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Daisy Murray
Digital Fashion Editor

Daisy Murray is the Digital Fashion Editor at ELLE UK, spotlighting emerging designers, sustainable shopping, and celebrity style. Since joining in 2016 as an editorial intern, Daisy has run the gamut of fashion journalism - interviewing Molly Goddard backstage at London Fashion Week, investigating the power of androgynous dressing and celebrating the joys of vintage shopping.