They're Jesse & Joy. ^^
This things never happen to me, really.
But yesterday, I went to Devlyn because I need new glasses (I can't see anymore, and I just found out my eyes are in 5 and 5.25 XD).
So, as I was really thirsty, I went to the food court to buy something, and Mix Up is just before the area, so when I was passing by, I heard a lot of conmotion coming from inside, and I saw a camera man walking around. I went to buy a coke and when I came back I saw that Jesse & Joy were singing inside. 
I was so excited, I've never seen anyone singing in Mix Up or anything.
Actually, I never get to see singers unless I pay for a concert.
So I was really happy yesterday.
And I got the CD, because I wanted to buy it long ago but I didn't got the money, and yesterday it had a discount for the event and everything.
^^ happy, happy cat.