It's a lot of things combined. Yes, obviously some heavy hitting tippers, and yes she's been around since... 2010 I think(?) so she has built up a following. (I remember watching her during her first weeks, her name was Aspen90, back when she was just like the rest of the new girls getting the hang of things! #nostalgia.) She puts on good shows (after hefty countdowns that she can make 99% of time), done many exciting g/g shows, is the face of
myfreecamsTV, has good content and clubs to offer, and as
@StrayObject mentioned, has done other adult industry appearances.
She also presents herself in a very bubbly energetic way the majority of the time, which is pleasing to many people who go to MFC for a happy escape.
She's kind of a big deal.