Hey man, if Goofy's a dog, then why can he drive a car and play golf with Mickey, and Pluto has to live outside?
It's a long story..
You see, Pluto was originally a normal dog who stood on two legs, wore clothing and communicated, much like Goofy. The only problem was that Pluto was originally known as Kim Han Plui and was born in Chongjin, North Korea. Kim Han Plui was born in a normal home with a mother, father and siblings. Kim Han Plui enjoyed several privilegies, since his grandfather had fought for the North Koreans in the Korean War. Kim Han Plui had been doing great in school until the day he was taken away by guards and thrown into a concentration camp. At first Kim Han Plui was confused, but then he got to know that his father had collaborated with the South Koreans and as thus, his entire family had been punished.
The camp guards decided to execute Kim Han Plui's female family members in order to show the consequences of his father's actions. Kim Han Plui got so shocked by this event, that the only thing he could say afterwards was "AAAAAAH" although it usually sounds like a bark. Despite his language disabled, he otherwise managed to have an healthy mind and could still think rationally.
After several weeks of endless labor Kim Han Plui saw his father getting shot after giving up on working and life. He decided to escape with his last family member - his brother. The camp guards had ordered them to pick lumber to bring back to the camp, but instead of that he and his brother decided to flee. As they approached the border Kim Han Plui fell down on the ground, just as a bullet was fired on him. Instead of getting shot, his brother had gotten the bullet in his head and instantly died. Kim Han Plui managed to stay down for a couple of hours in order to get the guards away.
As he swam over the river leading to China he came across an American tourist: His name was Mickey Mouse. Mickey Mouse saw Kim Han Plui naked, malnutritioned and dying. Mickey Mouse decided to help Kim Han Plui with hiding from the North Korean regime and took him home. He renamed him Pluto so nobody would be suspecting anything. Unfortunately for Kim Han Plui, Mickey Mouse was the only American he knew, and Mickey Mouse took advantage of this. He decided to use Kim Han Plui as a slave to fetch him food, his newspaper etc., and if he didn't oblige he would be sent back to North Korea.
As for the others, they just believe he's a duck.
How about Twilight Sparkle instead :D
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