An animated Harry Styles lights up London's O2 Arena

Even though only 300 of the 20,000 tickets for each night are general admission, a Harry concert is a day out. Groups of friends reunite, and internet friends meet for the first time – all running to hug each other. No romantic comedy could write an airport reunion scene as moving as the scenes from throughout the day.

The support act for these shows is the singer Mabel, and it's an odd fit. Harry's music has a decidedly classic rock vibe, whereas Mabel's style is closer to those of Styles' One Direction bandmates Louis Tomlinson and Liam Payne. However, this is an open and receptive crowd, and the fans give her everything they have. They dance to her song "Bedroom", and they sing along with hit singles "Fine Line" and "Finders Keepers". As she walks off stage, grinning, Mabel leaves the room energised and the crowd even more excited than they’d been 40 minutes before – certainly an impressive feat.

Before Styles and his band arrive on stage, the One Direction song "Olivia" plays over the speakers. It is undeniably one of the night's highlights, as everyone comes together to celebrate the love that brought them here. As the song finishes, the screen on the stage lights up and an animated Styles appears. We spend 15 minutes watching him attempt to solve a Rubik's cube, the anticipation building. He never even completes it, the amateur.

Styles may not be any good at solving puzzles, but he's pretty fantastic at a whole bunch of other things. He knows how to put on a show, for one. The man prances around stage in a pink and gold glitter jacket, a mix of Prince and a Disney prince. It is exactly eight years since a 16-year-old Harry Styles from Holmes Chapel auditioned for the X-Factor, and it is impossible not to think about the difference between that teenage boy and this man in front of us. Whereas at X-Factor Bootcamp he danced in the way most self-conscious teenagers do – awkwardly and awfully – now he skips, bounces, and moves his hips however he pleases. He is comfortable in himself and comfortable on stage. It is impossible not to be proud of him for that.

Mid-set, Styles and his lead guitarist – Mitch Rowland – make their way towards the B-stage, Mitch high-fiving fans and Styles blowing everyone kisses as they go. It is the most beautiful part of the night as they play the tender "Sweet Creature", alongside One Direction’s best ballad "If I Could Fly". What makes it so special is the fans, who have organised a project to light the room up as a rainbow – sections of the room have different coloured papers and they use the torches on their phones to make it glow. It is something that, somehow, the fans make happen night after night on the tour, and it is a testament to the power of young women working together that it works.

It is evident that Styles is aware of just how incredible his fans are, as he continuously thanks them. Towards the end of the show, he jokes that he wouldn't be allowed to get up on stage if people didn't come to see him, and insists that he is "in love with" every single person in the room. Of course, most artists know to thank their fans these days – after all, they really wouldn’t have a career without these people – but it doesn't feel forced or rehearsed (though admittedly Styles makes a similar speech each night of tour). His voices cracks as he says it, and the love he has for the fans is clear in the way that he interacts with them. Throughout the night he waves Pride flags around on stage, talks to people in the crowd, and at one point has the whole arena sing Happy Birthday to two girls. He gives everything he has, and when he says he "does it all for each and every one of you", he’s being genuine.

The encore begins with "From The Dining Table", during which the crowd softly sings along – but there are no claps, no screams, no cheers, just 20,000 people listening and appreciating Styles' voice and the heart he puts into his performance. The harmonies of Clare Uchima – keys – and Sarah Jones – drums – are clear here, and it's enough to make your hairs stand on end. They follow this with a cover of Fleetwood Mac's "The Chain", before closing with fan favourite "Kiwi". These last five minutes are wild; people singing, dancing, and jumping like it's their last five minutes on earth. For some, it may feel that way: Harry Styles and his shows are a safe place, somewhere people are free to be themselves and do what makes them happiest. Not everyone has that freedom elsewhere, so they make the most of this while they can, and Styles encourages it in every way he can. As the arena slowly empties out, "I'm so happy" can be heard coming from all angles and from mouths of all different ages. At a time when the world is terrifying and overwhelming for everyone, to hear that phrase coming from so many people is possibly the most beautiful thing of all.