Toots the cat is delighted, shocked and awed by the Zoot Cat knocking at her door. It’s really Tom in a home-made outfit. Here is one second (24 frames) of her reaction.
Ken Muse used the little overlapping upper lip (see first drawing) when he drew Mr. Jinks some years later at the Hanna-Barbera studio. Muse wasn’t exactly known for these exaggerated takes, though I can think of one he animated of Jinks in “Judo Jack” at Hanna-Barbera. Muse, of course, didn’t do all these drawings; he would have an assistant and an in-betweener. I don’t know who his assistant was.
Sara Berner plays the girl cat; Jerry Mann provides the male dialogue.
P.S.: I gather this is a "colour corrected" version of the cartoon and this colours are not correct.