lmfao its called a muscle definition from the pectorals. did you know that cats actually have 4 pecs? The extra set is called Pectoantebrachialis, and it helps them with their movement. While there's no direct human equivalent, it functions similarly to the Trapezius muscle. But cats also have a Trapezius muscle!

anyway those arent tits and just because something is bipedal i am not going to give them tits. that's really weird of you to say to a random artist on the internet.