
This only shows the characters that actually appeared in the manga; the East, West, & Dai Kaio appeared only in filler & movies; the West & North Kaioshin only appeared in filler, as well.
According to this chart, it appears all of the Kaioshin are collectively responsible for all of the Kaio. More accurately, Dai Kaio answers to the Kaioshin as a group.
There doesn't appear to be a one-to-one ratio for Kaio-to-Kaioshin. The thick-dotted line shows a subordinate/helper relationship (Kibito to the Kaioshin; Mr. Popo to Kami; Bubbles to North Kaio).
The trickle-down from the Kaio makes sense. Our North Kaio is specifically responsible for Earth's Kami, as well as anyone else in the Northern Galaxy. For a comparison, Paikuhan came from the Southern Galaxy, and therefore fought for the Southern Kaio.
Enma's off in his own little area, since he's somewhat separate from the rest of them in what his other-wordly job is. And Karin... well... he's just a cat from Earth



