The biggest reason I liked this was that one of my cats (Jazz, aka "The Variant") did the exact same thing when she was right around the same age. At the time I was living in an upstairs apartment in a big, beautiful old Victorian house with one of those big, enameled cast iron bathtubs but no shower. So my cats would sit and watch me take a bath. (ewww, I know)
One time after a bath the tub was still draining and had a couple of inches of water left in it. Jazz came over to investigate. She starts eying it and her butt starts wiggling like she's getting ready to jump in. I tried to warn her: "No Jazz. Jazz. You don't want to go there. Jazz, no." She looks at me, looks in the tub and jumped in, anyway. In one motion she jumped right out. BOING! and ran like the blazes ...
Her sister, Molly (who has always been the smarter of the two) just lied there and looked up at me as if to say: "What a dumbass".