Harley Quinn debuted in Batman: The Animated Series in 1992, created by Paul Dini and Bruce Timm as the Joker's quippy, baseball-bat-wielding sidekick, and Arleen Sorkin's bubbly Brooklyn voice made her an instant fan favourite. The character outgrew a one-off henchwoman role to headline comics, films and games, and short voice bites like this singsong farewell circulate widely on soundboards and meme pages. Creators favour it because it condenses her whole persona, sweet, chaotic and a little menacing, into under two seconds of instantly recognisable audio.