Master Sword was born in Manehatten. He was always cared for by his mother, but his father, being a drunkard, a cheater, and a poor parent, had never liked him. His father would always insult him, hit him, and call him gay, because he never had a girlfriend in school. However, he always cared about Sword's brother, Chimney Sweep, who always wanted to be better than Sword, and he always did one up Master Sword in everything he did. Cookie Crumb, Master Sword's young sister, always cared about him, just like his mother, but was always scared of him when he got angry. Due to how Master Sword was treated, whenever he gets mad, he would almost kill someone, or even end up killing them, due to his short temper. But, he usually tries to calm himself down before he does this.
After he passed school, he went to look for work. Though, due to not being much of a hard worker, he was never able to get a real job. Finally, he found work with a man named Cut Purse. Master Sword was told to meet a man and hand him a suitcase. Master Sword wa told by Cut Purse to not look inside. However, while at the meeting place, he did look inside, only to see a large amounts of money inside. Master Sword, wanting to use the money for himself, took the money, ran off, and pretended to have given it to him. By doing this, Master Sword unleashed a deadly war against the opposite crime family. Sure enough, Master Sword was blamed, as he was shown on a secret camera to have stolen the money, and was nearly killed by Cut Purses's goons.
After this, Master Sword went into hiding and ran off all the way to Ponyville, hiding from Cut Purse, who is still wanting to kill him. Here, Master Sword met the members of the mane 6. He easily got along with them, and always enjoyed meeting them. However, he had a crush on a pony named Derpy. People thought it was odd for him to like her, and not any other ponies, but Master Sword quoted, "Quite frankly. I don't give two fucks".
Master Sword also met her cousin, Saten, and they both, with time, became sort-of-good friends.
Another person he met in ponyville was a pony named Unknown, who was a unicorn that also looked almost like him. Unknown did his best to try and steal Master Sword's bank account, but only managed to get stabbed by Master Sword and thrown into the ocean, presumed dead.
Master Sword still lives in Ponyville, trying to hide from Cut Purse and his goons

Personality: He is loyal, humorous, and very friendly to people, but when he is angry, he is psychotic and very violent

Relationships with other characters:
Twilight: Master Sword was first greeted by her, and was always glad to see her.

Spike: Being the first boy he met in Ponyville, they both got along very quickly

Applejack: Though, with her being honest about his personality (She said he was real crazy) They still managed to be good friends

Rarity: It took some time for them to be friends, as Master Sword had bad taste in clothing (He doesn't wear any)

Pinkie Pie: Finding her wacky personality humorous, they got along quickly

Rainbow Dash: At first, they were both wanting to prove who was better with an arm wrestle. Only after nearly killing each other, they both laughed and became friends afterward

Fluttershy: It took some time for Fluttershy to get used to him, but after Master Sword became friends with the others, she began to be friends with him

Derpy: Master Sword always had a crush on her, but never did try to tell her, but instead, gave her hints. She never did get them

Saten: Being an odd pair of friends, as they always seem to try to get on each others nerves as best as they can, but they are friends nonetheless.