When two or more cats live together, they see each other grooming each other's faces and bodies, and this act of licking each other is called allogrooming. When a cat does allogrooming, its favorite part is concentrated on its small face The allogrooming is made of the optimal size and shape to groom every corner of the narrow face. The thickness and length of the handle are also considered to be able to hole the brush from various angles in consideration of the cat's various posture.