I really like the fluff for the class. The abilities and the backstory are all solid conceptually and I very much approve. Linking to rakshasas is cool and I wasn't aware of that association for those guys.

You need to specify what maneuverability of flight the wings grant. I would advocate average.

The natural armor bonus from ceremony of flesh is too high, especially considering it stacks with everything else. Drop it down to a +1 increase or make it a +4 or +5 enhancement bonus to natural armor. Similarly, the regeneration makes the guy basically never require healing again from some sources and should be made limited-duration (such as for 2 rounds per level, activated as a free action).

I disagree with Mulletmanalive and think you should return the capstone to being 1/day.