I really hope he remembers that he wanted a water pet, and refuses to take this young master dragon... dragons are cool, but only when you don't pick em just cuz they're a dragon, but cuz they match what you need/want.
The first on the list was a sponge. This seems like it might have to be the hardest working to live up to being an Overlord Race. And therefor match Shi Yu's personality, and the Unscientific Theme, the most.