He went back to Tafe to finish school a few years later. "On the second day I met this dude Dylan who was a rapper and I'd never met a rapper before but he had pot. Pretty much. So he said round to my house and we'll smoke pot and we won't go to school, and I said 'That's perfect'. And I went back there and we started freestyling and that was it."

nce his first release, 2008's The Waiter Minute EP, to his 2012 debut LP, This Was Tomorrow, Sentry has become known for his densely packed rhymes, which are simultaneously clever, fast and witty. Which all means writing doesn't come fast to him. "I'm pretty slow with the writing. I want every line to count, and every line to be able to be scrutinised on its own. And that's why I do it, because I'm extremely analytical and it p---es my friends off no end. If I listen to a song I just analyse the f---out of every line and I kind of just assume that everyone's going to do the same to my stuff."

In fact, in the weeks before a tour, like the upcoming Groove In The Moo festival run, Sentry begins a training regime of running, just so that he can keep up with his own rhymes onstage. "Being onstage is exhausting, and I'm not the fittest dude," says Sentry, who's favourite thing is to get stoned and play computer games. "The way that I write, there's not a lot of breathing room, and I always think after I've written it, 'f---, that's right, I was going to write it a bit more sparsely so that I can actually perform it live without passing out.' But I never do."

He's never actually passed out onstage, but he did almost throw up once. "From the exertion. That was pretty sick. Because there's no-one else there with me, I want to fill that stage, and I'm kind of pretty energetic anyway so I'm just running around and trying to rap these really tricky verses. I didn't puke though. I didn't puke, I held it down."

There's a website called Rap Genius where hardcore hip-hop fans spend hours analysing the music of their favourite MCs, and not surprisingly, Sentry's intricate rhymes get a lot of attention. "There's dudes on there typing my raps in and debating what each line means and shit which is really cool," says the Melbourne MC. "And they made me sound smarter than I actually am, which was great. They're like, 'I think this means this and that means that, and directly juxtaposes this line' and I'm like, ...! It didn't at all but yes! Keep going! You're right!'"

SETH SENTRY

When: March 14, 8pm

Where: ANU Bar, Acton

Tickets: $37.21 + BF available from ticketek.com.au