Would it just always get the boost? And would it remove comatose ability to let it sleep?
The Pokémon with this Ability takes double damage from Hex and Wake-Up Slap; can be affected by Dream Eater, Nightmare, and Bad Dreams; and cannot successfully use Rest. However, due to not actually having the sleep status condition, the Pokémon with this Ability is not considered to have a status condition for the purposes of effects such as Purify and Chesto Berries.
Source
It will take double damage and not wake up.
Hope this helps! :)