Quesadilla Faldo is Waldo Faldo's sister and Weasel's former girlfriend. She only appeared in Stormy Weather. According to Waldo, she was born in a Taco Bell restaurant for unexplained reasons, and would have been almost named “Burrito Grande”. To him, that would've been a terrible name.
Quesadilla was implied to have met Steve in Twinkle Toes Faldo alongside another sister named Noxzema Faldo