Gyomei Death. A good ending for gyomei *spoilers* manga discussion. He is voiced by tomokazu sugita in japanese version and crispin freeman in english version.
There can be no doubt that gyomei himejima is the strongest demon slayer character ever. He has short black hair, below which is a scar that runs horizontally across his forehead. There are only two demon slayers who became hashira in only 2 months of joining the demon slayer corps, one of them is gyome which again shows how strong and capable he is.