reaper sans

looks like

Reaper Sans is a skeleton that wears a black hooded robe similar to what you would figure a grim reaper would wear. And with that he has a rope around his waist and around his neck hanging loosely with a small gaster blaster on it. He also doesn't wear shoes. He can have black wings appear and disappear for flight.

powers

Likely Omnipresent: Exists as the conceptual manifestation of death itself, meaning he is everywhere that death exists, he and Papyrus were also directly stated by Gaster to be everywhere, although it may have been metaphorical more than literal. Death Manipulation: Existing as death itself, Reaper Sans is capable of negating natural forms of durability, and instantly killing nearly any creature with a soul. He can also kill most creatures with a touch. His Scythe, similarly to his own attacks, can negate natural forms of durability, and instantly kill nearly any creature with a soul. Immortality: Does not age and can likely reincarnate or resurrect even if killed. Non-Corporeal: This word means to have no material body or form. Reaper's body is therefore like a ghost; you can't touch him, and it's impossible to hurt him physically. Trying to do this will lead to you going right through him.

personally

Sans was okay with what he had. Reaping sinful souls had been what he'd done for the past centuries, and he didn't enjoy it, but he could manage it. Unfortunately, after he had accidentally killed the person he loved, he went crazy and suicidal, with bits of his soul lost. Toriel helped him, getting back his sanity. However, his soul is still not complete, and he is still partially insane. He is back to normal, for the most part. He still can become uncontrollable and temporarily crazy sometimes, though. Sans doesn't like his job, but tries his best to hide it. He is calm most of the time and hides his feelings. He can be nice and funny once you get to know him. He has a fear of dolls and clowns. Reaper is very scared of Gaster.