Selling out a UK and European tour in 10 minutes flat would be a landmark moment for any artist. But, for blossoming pop star Alessi Rose, it's arrived totally out of the blue. "The headline tour is definitely the thing that is burning a hole in my brain right now," she marvels. "I can't fathom this is real."

Considering she's only a year into her career, she's quickly making fantastic strides. While Alessi's been writing for as long as she can remember, it's the professional reality which has felt like a whirlwind. "Doing it firsthand feels like it hasn't been happening particularly long. So this last year has been mental for me!" With her head still spinning, particularly after a disastrous day featuring a three-wheeled suitcase and falling up some stairs, she's ready to digest the dream.

2024 is the year the 21-year-old managed to get her career swiftly off the ground. It has involved a cloud of candidly earnest social posts, her debut headline tour, supporting Noah Kahan in Belfast in front of 40,000 people, and releasing her debut EP, 'Rumination As A Ritual'. This early project encapsulated her move to London to chase her musical ambitions (and to study poetry at university, of course). Hailing from Derby, where she was raised by an 80s new wave-loving mum and a country-loving dad, when she was younger, she also discovered her love of reading and writing: "Writing poetry was how I got into writing lyrics," she says.

A starry-eyed person, her ambitions are as bold as her lyrics are honest. "When I was living at home, people would be like, you can be the biggest person to have come out of Derby, and it's like, I don't want to put a cap on it," she smiles defiantly. "I just want to be the biggest person."

Part of that journey is figuring out her artistry, for which this year has offered her clarity. "I've come to realise I love making music, I love being on a stage, they're all my favourite things," she says. "It's hard to even explain it. Ever since July, when I did the support for Noah, that was when everything amped up. And then doing the tour and having these rooms full of people who were there to see me perform and hear my music, I hadn't experienced that before."

Alessi has had a penchant for performing for much of her life. "I was always on a stage as a kid, but more in a musical theatre or a choir or dancing," she explains. "I used to have the worst stage fright ever. I used to be like full body shakes and couldn't function. And then when I started doing my own music and performing my own songs, I was like, 'Wait, I feel confident now'." After a summer filled with her first festival sets as well, including a packed-out set at Latitude, the fact that her second headline tour has not only been upgraded but then proceeded to sell out proves that Alessi has tapped into something.

Alessi's songs are pivotal to this rise. Vibrantly opening up her life, Alessi is giving us front-row seats to witness the warts 'n' all of being young, in love, and dealing with the messy, tea-soaked fallout. More importantly, this is all expressed through an addictive concoction of gritty pop-rock and the occasional reflective stripped-back attack. It's entirely diaristic, a lore-building enterprise that fizzes with life. Or, as her social bios state: "if people don't want me to write songs about them they shouldn't do bad things".

She has songs about girls she hated in school (the heartfelt 'Lucy') and boys who've wronged her she can't quit (alt-pop charged 'eat me alive'), as well as turning the tables (the Olivia Rodrigo-tinted 'CRUSH!'). It's the approach she's taken to building her fanbase: be utterly transparent. "I will post whatever thought pops into my mind, no matter if I should have kept it to myself or not," she cackles. "They're wonderful - insane - but wonderful, like me," she smirks as if butter wouldn't melt.

There's a camaraderie in Alessi's understanding of her fanbase. Throughout her live shows, and beyond, she's arranged hang-outs where she could meet her fans, as well as inviting them to the studio to hear works in progress. "Seeing a bunch of girls clutching their best friends, swaying, crying, in close proximity, it was making me want to sob every night," she fondly recalls. "There's definitely a big through line of friendship and togetherness and girlhood and being in it together. I think that was why I flocked to people like Gracie Abrams when I was younger."

It was hearing the likes of Gracie Abrams singing about her experiences with OCD that gave Alessi the confidence to embrace her own. It also gave her the spark to start recording and uploading clips of her performing in her makeshift bedroom studio, unknowingly creating the chain reaction that's led to this career of hers. "I always said to myself, if I ever get to be in a position where I have people who care about my lyrics and care about what I have to say, I will be open about it, because I thought I was the only one. I thought I was crazy," she recalls. Now Alessi's able to be the same for her own gathering fanbase. "[That's been] a huge thing for me, getting messages from 14-year-old girls being like, I have OCD, and I've never found anyone who's spoken about it so frankly."

Over the past year, Alessi has noticed her fandom growing into the same level of dedication she focused on her favourite artists - down to them piecing together pieces of streams of new songs to create a "black market Soundcloud playlist", she laughs. "There's a playlist somewhere of the 'Alessi Rose Archives'. It's hilarious. There's a few fan favourites on there. Like a song called 'Start All Over', which they've been campaigning for me to release for what feels like a year, but I think I only wrote it in March."

Not one to hang about, Alessi's more than happy to keep scribbling away writing songs. While 'Rumination As A Ritual' will always be close to Alessi's heart ("I love her, she's my first child"), its follow-up is where she's processing her more up-to-date life. For her upcoming second EP, 'For Your Validation', her journal is open even wider. "I feel like there's more honesty in this one," she explains. "A lot of them are about similar things. They're all very honest and very specific."

Writing for this new project also opened up a new door for Alessi in terms of understanding that there is indeed now an audience listening to her every word. "Taking into account this new position of being like, 'Okay, I'm an artist now'. I want to be the best role model for all of these young girls. I want to be the best daughter to my parents, who I want to be proud of me all the time. I want everyone to be like, 'You're doing a good job'. That's what my mum always jokes; I have always needed a metaphorical gold star for everything."

Well, it shouldn't be long until she's got a ream of gold stars plastered across her various notebooks. Alessi is driving fast towards a future she's ready to embrace. She knows more levels of her craft are waiting to be unleashed. "I love that music is now in a place where people are being allowed to reinvent themselves in a way that still allows them to be consistent," Alessi explains. The likes of Taylor Swift have established this for a new generation of eager listeners, but for Alessi, the benchmark is Madonna. "I love [her], [she] reinvented herself every single album," she says. "And it's really fun that we get to do that."

And while she's still in the throes of completing her university course ("I'm getting this degree by hook or by crook," she laughs), music, as it always has been, will be her priority. Alessi Rose is just getting started: the pop world is hers for the taking, and the ride is ours to enjoy. "I think I know what's the core," she reckons on just who Alessi Rose is. She's achieved an enviably fervent fanbase far earlier than anticipated, and now, she has the bedrock ready to build upon. "There are so many ways that it can grow, and I can write in so many different scenarios," Alessi ponders. "I haven't figured it out myself yet. But it's going the way I want it to, and I'm grateful that my audience are people who are open to me figuring my shit out still."