katlák je mokot
When you see Matllafous, you usually say this. The explanation is, that the original expression "matlák je kokot" has switch its first letters, so it sounds more funny. "Matlák je kokot" means "Matlák is a cock".
person1 : "kostiku, co je katlák?"
kostik: "katlák je mokot"
kostik: "katlák je mokot"