Salazar Slytherin
Salazar may not have had a date, but he did not want to miss out on a party... and the ability to spy on Ava and Frankie. For the occasion he dressed as Prince Rhaegar from A Song of Ice and Fire, complete with the three-headed dragon helmet, which served as his mask. Salazar even went as far as to change his hair from short and black to long and silver blonde. He had told no one of his costume idea, wanting to remain anonymous. As much as he loved himself, it was going to be fun to be someone else for an evening.
Immediately upon entering, Salazar went to get himself a beverage. As he stood there sipping, he appraised everyone else there, looking to see who he would ask for a dance. Occasionally, he would look around for his daughter. He had every intention of letting her have fun tonight, as long as he felt Frankie was behaving himself.