The humor in this meme may stem from the juxtaposition of the character, who is an extraterrestrial from the television series 'ALF', known for trying to eat cats, with the text that plays on the double meaning of 'illegal aliens'. The phrase typically refers to people who have entered a country unlawfully, but here it humorously refers to an actual alien from a TV show, and the situation being fiction is labeled as 'good times', which might be amusing due to the absurdity of such a time ever existing.