Ed Sheeran seems to have raced from obscurity to the top of the charts almost overnight.
If Ed Sheeran has an entourage, it certainly doesn't feature a stylist or a hairdresser.
Sporting scruffy, just-out-of-bed hair and wearing the same clothes he's "had on every day for years", the singer-songwriter looks more like a disgruntled paper boy than your average chart-topper.
He doesn't talk like most pop stars either. In an age of mundane, media-trained drones and young, vacuous 'talents', he's refreshingly honest.
That's not to say Sheeran sits around slating his peers, delivering snarling Liam Gallagher-esque sound bites to anyone who'll listen, but he's a thoughtful conversationalist. And considering the fact he's still only 20, and has been interviewed 10 times every day for the past six months, that's impressive.
"I'm not afraid of hard work," he admits. "I'm not ashamed to say I'm hugely ambitious, and I dream of Coldplay-sized fame. Their music has grown to fill the venues they're playing - from rooms to arenas to stadiums, and that's where I want to be one day.
"I know it's all about the songs, though, and the amount of work you're prepared to put in. And I'm fully prepared to put the effort in."
Sheeran's no stranger to hard graft, and his story is an endearingly old-fashioned one.
To the casual observer, his 'journey' from bedroom obscurity to 100,000 sales of his debut album '+' was something of an overnight sensation.
In reality, Sheeran started seriously planning his rise to stardom four years ago when he was just 16.
"I first picked up a guitar when I was 10 or 11," he explains. "I picked up a few chords and quite quickly started writing my own songs using other people's chord structures.
"By the time I was 14 or so I thought music was something I'd like to do, and then by 16 I started to think it was something I could do. That's when I took all the big risks."
In 2005 Sheeran, who was born in Halifax, West Yorkshire, and moved to Framlingham in Suffolk with his Irish parents as a small child, released his first EP, The Orange Room.
This was followed by four more independently-released EPs, two albums (2006's Ed Sheeran and Want Some? in 2007) and, in 2008, a move to London to concentrate on playing live shows.
Sheeran also worked as a touring guitar technician for Nizlopi - remember The JCB Song? - and went into competition with James Morrison.
After reading an interview with the gravel-voiced You Give Me Something singer, who claimed to have played 200 gigs in a year, Sheeran wanted to do a bit better.
"I played 312 shows in 2009," he says. "Sometimes to no one, or five people, often to more..."
Aside from a hard slog, the key to Sheeran's current success seems to be word of mouth. Thanks to his constant gig-playing, he's made more than a few high-profile friends.
During a trip to Los Angeles, he met Hollywood star Jamie Foxx, who duly invited him to spend the rest of the day recording at his house.
Rio Ferdinand has been a vocal supporter, as has Elton John. Crucially, it's been the stars of the UK grime and hip hop community who have adopted Sheeran as their own.
Read any interview with the likes of Wretch 32, Devlin, Wiley, Tinie Tempah or scene kingpin Labrinth and they'll all drop their friend's name into conversation.
On the surface, it might not seem like acoustic guitar-playing Sheeran, from a rural Suffolk idyll, and the rapping stars of a music genre born on the streets of London, would have much in common, but looks can be deceiving.
"I think if you take away genre barriers, good music is good music," says Sheeran. "If you're a bad lyricist, I think someone who only listens to acoustic music would recognise that in hip hop just as much as someone from the grime scene would recognise a bad singer-songwriter.
"I think it's a situation where musical talent recognises other musical talent."
His storytelling is perhaps the most obvious link to Wretch and Labrinth - both artists he's collaborated with. Many of Sheeran's songs are socially conscious streams of prose about being young in modern Britain, all of them autobiographical, like The A Team, which reached No 3 in June this year.
"I have a friend who works at a homeless shelter every Christmas," he explains. "He asked me to go along one year and play some songs for the people there. I met a girl called Angel, who was this amazing girl who really stood out - mainly because she was the only girl in the shelter and everyone else was male.
"She was kind of like the police in the shelter, what she said went, but she was always breaking the rules so the guys running the shelter had to strike a deal with her to get her to behave.
"I learned a lot about Angel, the unfortunate ways she earned her money on the street, and the things she did with it when she had it - it was a very bleak story. I spent some time with her playing her favourite songs, and then wrote The A Team for her.
"The lines in the song, 'She don't wanna go outside tonight' and 'It's too cold outside for Angels to fly' are about her having to go back on the street in winter when the shelter closed down after the Christmas period."
There's also You Need Me, I Don't Need You, a bitter rant against his ex-manager.
"I feel like sending him a plaque now the album has sold well. Let's just say there's no love lost between us," he says.
"For me, though, writing personal songs is like therapy, just to get it all out. That's my justification for writing it, and my justification on releasing it is that there might be someone out there who feels the same way.
"I'm never going to feel worried about releasing those feelings to the general public."
Sheeran has amassed legions of supporters who have followed his gradual rise and feel especially loyal as a result. Their support is not wasted on him.
"Everything I do is for my fans," he says. And in response to negative criticism of his recent album in some quarters of the music press, he adds: "I don't make music for the critics.
"They didn't spend a tenner on my album, they haven't come to my shows for the past few years. A lot of those guys probably listened to my album once or twice and that was that, and it shows when they make assumptions about the meaning of some my lyrics.
"Well I don't care what they think. If a fan came up to me and said they didn't like what I'd done, then it would hit me and I'd take it in and think about it.
"Obviously not everyone is going to like what I do, but things seem to going pretty well so far."
:: Edward Christopher Sheeran was born on February 17, 1991.
:: In 2008, Sheeran auditioned to go on ITV1 series Britannia High. He's probably glad he didn't get through - the series was widely rubbished.
:: Earlier this year Sheeran announced a show at London's tiny Barfly venue. More than 1,000 people turned up, so he played four sets so everyone who came along could see him, including one performance on the pavement after the venue had closed.
:: Sheeran made his debut on Later With Jools Holland earlier this year, performing alongside PJ Harvey, Lykke Li and Ron Sexsmith.
:: To celebrate going to No 1 last month, Sheeran treated himself to a Lego Millennium Falcon Star Wars toy. "I'm not very materialistic," he says, "but I enjoyed making that."