Dorothy and Roger are the mascots for Mars Schmackos in Australia and New Zealand. They were originally stop motion animated and first appeared some time in the 90s. Dorothy is a woman who loves her dog Roger and when she wants him to do something she'll bring out Mars Schmackos and says "I'll give you a schmacko" and he'll do what he's told. There were a few other characters too that had dogs and the owners would do the same but they were not the main mascots.
Dorothy and Roger stopped being featured in the ads sometime in the 2010s and their ads were replaced by an odd and ridiculous live action ad from 2017 until 2020 when Dorothy and Roger were finally brought back in CGI but made to look stop motion as a homage to the original campaign.