It was a very good idea for the café owner to put his wife behind the counter. The customers came in droves. Yes, the nymphomaniac wife had always demanded more attention, but now it was good for business. Her charms were always in business, the coffee sold as well as alcohol, and even had its own regulars. Even a barista could achieve fame if her husband didn't mind.
The brown-haired girl is not an ordinary modest girl. So she showed off her skills in front of her lover. Apparently she has a lot of experience.