Quote Originally Posted by Alberel View Post
Go and re-watch the cutscene. You literally see Lahabrea's dark aether get absorbed into the eye. If he were destroyed as the others were his aether would have been outright destroyed by that of the light but it wasn't.
Except Elidibus outright says to himself that Lahabrea was slain. Even if you were to ignore that part, primals in general need aether to sustain themselves, so it would act like fuel. Ergo, Lahabrea got burned off as extra calories.