Cain

Cain is the brother of Abel and a retired demon known as the Father of Murder who used to train the The Knights of Hell. He and his brother  are also the direct ancestors to Sam  and Dean.

Personality
Cain showed the most humanity  than any other demon on the show.He had fallen in love with Colette a young woman who loved him as much as he loved her.Beacuse of her Cain retired,but Abaddon tried to convince him to join the knights.Cain rejected her offer and Abaddon possesing Colette made Cain attack her when she vacated her body and Cain killed Colette with the First Blade.He made Colette a promise to leave the demn life behind.At his house when he killed an army of demons he expressed a death wish due to breaking his promise to Colette.He helped Dean after all seing himself in him the two have alot in common.So he gaved The Mark of Cain to Dean,dean being the person to kill Cain.He showed a affinity towards bees.Him being a beekeeper.

Powers and Abilities
As one of the oldest to appear and the first Knight of Hell, Cain is an extremely powerful demon. His reputation alone made Crowley reluctant to go anywhere near him, opting that he and Dean go "a world away" from Cain as possible. He could kill other demons with a mere touch. He could even prevent Crowley, the King of Hell and a powerful demon himself, from escaping and speaking just by a simple gesture. His strength was also shown when he killed an army of demons single-handedly.
 * Immortality - Being one of the original humans as well as one of the original demons, Cain is at least 9,000 years old. He hasn't aged since well before 1863.
 *  Demonic Possesion  - He possesses humans to exist on Earth. He had been in the same vessel for over a hundred years.
 *  Super Strength  - Being the original Knight of Hell, Cain is considerably stronger than lesser black-eyed demons, casually overpowering and lifting one off his feet with one hand and snapping his neck with very little effort.
 *  Telekinesis  - He could move objects by snapping his fingers.
 *  Teleportation  - He teleported from across a field to beside Dean and Crowley and then to Collette's grave and back.
 *  Terrakinesis  - Cain's arrival could create local tremors.
 * Weather Manipulation - His arrival could also cause sudden gusts of y
 * Demonic Smiting - He can kill demons with a touch similar to angels. Except in Cain's case, the color is red rather than bright white light.
 *  Immunity  - Cain is completely immune to the demon killing knife. Only the First Blade could kill him.
 *  Invulnerability  - Cain is invulnerable to normal and mortal harm.
 * Apporting- Cain was able to teleport Dean and Crowley outside with a touch.
 *  Power Negation  - Cain is able to negate abilities of weaker beings as he did with Crowley, trapping him inside and stopping him from teleporting away.
 * Demonic Control - Cain was able to strip Crowley of his ability to speak with a simple gesture.
 * Spell Casting - Cain was able to non-verbally enchant his house so Dean and Crowley couldn't leave, or the other demons couldn't teleport in. He could undo and recast this spell with a snap of his fingers.

Weaknesses

 * The First Blade:Cain himself states that the First Blade can kill him. To date this is the only thing confirmed that can kill or hurt him.
 * The Colt:As the Colt can kill all but five things in all of creation, it can presumably kill Cain.