An Illiez is a person who has a hair-do which when seen at first reminds of a hedgehog but then turns out to be a pretty chill haircut.
It is a very loving person that tends to make jokes that are funny for others but not for the person he did it on...
In other words be proud to have an Illiez friend if you have one
A+B hug but B pulls away weirdly
A is upset so makes a sad face
B: Jelly Fish!
A: OMG you are such an Illiez!