Susie is one of the main characters in Deltarune, Toby Fox's episodic role-playing game that followed Undertale, where she starts as a feared school bully before joining the adventure. Her laugh reflects that rough, confident personality, which is why players and editors lift it from gameplay for short reaction clips. It spread through soundboards and video edits where a single second of mocking laughter can sell a joke, and it remains popular because Susie is instantly recognisable to fans and the sound needs no dialogue to be understood.