Kaoru is a man with short black hair, medium thick eyebrows and a goatee. He normally wears a purple shirt, white trousers and a yellow apron with a donut logo and green suspenders and rims. He wears white flat shoes with grey tips. His eyes are mostly covered by his round black sunglasses.
Kaoru usually describes himself as somebody who does not sweat over the small stuff. He's laid back and easy going, but also passionate about his business and always ready to help Love and the others. He's not that fazed by the fact that Tarte appears to be a talking ferret, nor by Chiffon and her powers. He is also humorous, and ends most of his jokes with a weird laugh, though sometimes the Cures have trouble understanding him.
His age and his home is something unknown, partly due to his having a mysterious past of multiple careers including royal body guardian. When Love and others are upset, he plays the consultant role and encourages them. Owing to a contract that Tart can get doughnuts for free by watching the shop for him, he also shares the secret of the existence of Tart and Chiffon with the Pretty Cures.
- Karou is similar to Fujita Akane, since they both run food vendors where the Cures usually talk and hang out.
- He shares his given name with Kiryuu Kaoru, a character from Futari wa Pretty Cure Splash Star.
- Kaoru's late voice actor, Maeda Ken, passed away on April 26th, 2016.