Pixie is the house of those who consider theirself higher than others in intellect, beauty and skill. Pixies take enormous pride in their work and as such are incredibly humiliated when something goes wrong. They are especially adept at deceptive magic and will do anything to reach their goals. Their specialty magic lies in Imperius curses and love potions.
As it turns out, the Pixies, upon discovering that every other house, for a variety of reasons, had an exact duplicate in the Muggle world, vowed to outdo everyone. Unfortunately, their plan (which involved the fairly breathless assistance of some members of Igor House), backfired rather spectacularly, resulting in, at last count, 157 exact replicas of Aphrodite Heights scattered across the country, some in the middle of lakes, atop other buildings, and, in one very memorable instance, upside-down inside Giants stadium. Fortunately, the AAU security force was able to retrieve and destroy all but one of the miss-placed duplicates, and selected members of both Pixie House and Igor House were placed on academic probation. The Pixies went back to ignoring the Igors and life returned, more or less, to normal. Of course, the administration, when asked about the single remaining Pixie House duplicate, finds it much simpler to merely blame it on coincidence.