The first line of the Wikipedia entry for Jubilee states, "Jubilee had the superhuman power to generate 'sparkles' out of her hands..." So, that pretty much explains why she got the ax from Professor X (Pete Holmes) this week.
But as always, it's not enough for the professor to fire you, he has to humiliate you as well. After suggesting that Jubilee would be better suited for doing a light show at a Skrillex concert, he lobs one last insult: "You look like Hello Kitty's best friend... Goodbye Kitty."
Ouch. Watch the sketch from "The Pete Holmes Show" above.