Before becoming an animated series, in 2009, Sally and Chica were initially stuffed plush dogs who were filmed on camera by Aurelia when she was young.
Paul Stompbox auditioned for Scooter and Cody on 27 November 2015. He wanted to audition for all of the other male characters, but that day, he felt like going back to work on his Downfall Parodies Music Video which he uploaded on YouTube the same day. Later, on 22 December 2015, Paul mentioned in a comment on 5 Ways to Prank on April Fools (2013) that he saw the entirety of the 1st season of the series and that it "seems like quite an interesting animated indie show." The same day, Aurelia replied, "Thank you so much! We can't wait to work with you!" Paul got cast as Cody immediately afterwards.
Initially, voice actors for Chico, Crystal, and Charlotte were cast during the Season 3 casting call. Due to the actors "never writing back," Aurelia had to cast new voices for them in the Season 4 casting call.
In production, several characters were decided not to appear/cut, especially from Season 4, but Aureila has confirmed that she may have them appear later on. However, none of this is certain.
Paul Stompbox (Cody/Jasper), a huge fan of the series, made a Downfall (2004) Parody crossover between it and this series where Adolf Hitler gets sent into the Sally and Chica world and starts a havoc. It gained over 365 views and 10 likes within 30 days after its upload, which became even more popular than Modesty vs. Arrogance (2015), the most viewed episode the series at 167 views and 6 likes as of 24 August 2016. Aurelia saw the video and texted to Paul Stompbox on Skype, "I thought it was really funny. XD I liked it. X3".