My kao character evolved to level 100 then got reset to level 1. Can't we disable it or stop once I reach the top, or something? I don't pay much attention to it anyway. I just want to quiz.
It wasn't reset. When it reaches L 100 you get to raise a new kao-chan. The finished one should still be there; click the kao-chan image on your dashboard --> collection.
Kao-chan is linked to the daily challenges. As far as I know, the only way to disable kao-chan is to disable the challenges. You can do that under settings --> motivations --> turn off adventure mode.