In my world a mixer is the tonic that accompanies a gin, but in the land of under-18s it means you're a dedicated fan of four-piece British girl group, Little Mix.
Excited 'Mixers' responded warmly to support acts The Mend and Reconnected but there was no doubt about who exactly they were all there to see.
When Perrie, Jesy, Leigh-Anne and Jade arrived on stage the decibel levels soared and I thought my ears were going to explode.
I couldn't always make out what the girls were actually singing, but credit were credit is due, they can actually sing.
They have achieved quite a bit of chart success with their R&B, dance and rock pop sound, since winning TV talent show juggernaut X Factor in 2011 – the only girl group to do so in the history of the competition.
At Sunday night's sold-out gig – the final of their 20-date debut headline tour – Little Mix performed We Are Who We Are, DNA, Always Be Together and plus covers including TLC Scrubs.
I'm not the target demographic, so I didn't leave the Waterfront with a Little Mix doll or bag under my arm, but I can understand why the 2,500 strong audience of mainly little girls screamed themselves hoarse.
Little Mix are unlikely to come up with any groundbreaking material, and they may well just fade back to the obscurity from which they came, but while they are on the pop music scene, they promote a message of positivity and their fun songs are good to dance to.
The Waterfront auditorium was easily one of the happiest places in Belfast on Sunday.