Flippy and his evil side are a surprisingly popular couple.
Many fans like this pairing because it is a "love-hate relationship". Some believe that Fliqpy wants to protect Flippy and that's why he takes over and kills the other Tree Friends. It is a very couple as Flippy and Fliqpy are the same person/share the same body, however some fans do know this and still like the couple anyways.
Many haters point out that Fliqpy and Flippy are the same person. This is true, however, with how real the fight was to Flippy in "Autopsy Turvy/Double Whammy Part 2". It's not impossible to say that if he became more insane this "relationship" could seem just as real to him as well.