The ironic thing is, he started off pretty well sane. The fun in the manga is watching him devolve really. *Grins* Because boy, does he go downhill. I suppose tis a lesson in power as well.

Ive only seen u til episode six in the anime itself but yeeeah, Ryuuk summed it all up in the beginning when he said that the only bad person left in the world would be Light himself. :3

Im tellin ya, go to onemanga.com and look up the manga. It takes way more time, sure, but you can almost see the point where Light loose it. :3