>>149785151
There are many theories why pink and yellow specifically but it could refer to Money and Love, two things Spamton wants. The cat character, seemingly called FRIEND, will presumably play a part in the next chapter of Deltarune where he will help Kris' dad who also wants those things. In addition its the colors the Mercy text can be in undertale. Plus sometimes FRIEND's pink eye is cyan, which is the color palette of Catti, another cat character who might be related to FRIEND