As we may know, "Squee!" is a noise primarily made by an over-excited fangirl. Squee girls are a form of fangirls. Most enjoy anime and manga; several enjoy yaoi. They are known to glomp people, write/read fanfiction, and say such phrases as “w00t” and of course, "Squee!" Most seem to be tech addicts who use Geia and Livejournal. They are often misunderstood by those who are unfamiliar with their ways.
Some squee girl randomly tackled that guy in the Vash costume.