They will appear in part 1 of the Hiro Chronicles.
Yin has the power of light and Yang has the power of darkness. Yang will be Hiro's rival and have different views of being Renkai.

they are Renkai but they are different from the others. They aren't evil just misguided by the reapers

i playing the dofus online game used these two to play like them so much and thought about them a lot I wanted to add them to part 1 as soon as possible

their race are Pandanion