Shrek is the titular protagonist of the Shrek franchise. He is Fiona's husband, Donkey and Puss' best friend, the ogre triplets' father, and the son in law of Lilian and Harold.
Shrek lives in a swamp in the middle of the forest by himself. At first, he appears to like being by himself and enjoys scaring people, but not hurting them. Even though his background is unknown, it is assumed that most ogres hurt people, but Shrek isn't violent.
One day, in the forest, a talking donkey named Donkey enters Shrek's swamp, followed by a group of knights. The knights order Shrek to be arrested, but Shrek scares them off and saves Donkey. Donkey's grateful, and it's clear in the way he thanked Shrek repeatedly, staying the night outside of Shrek's house. However, more fairy tale creatures soon arrive and begin to dominate his swamp. Shrek learns from that that Lord Farquaad has dumped them all there. Outraged, Shrek takes Donkey and goes to his castle to demand his swamp back.
When he arrives at Farquaad's castle Duloc, he defeats a bunch of knights in a contest to see who will rescue the Princess, Fiona. When he wins, this intrigues Farquaad and he makes a deal with Shrek: If he rescues his princess, he will give Shrek's swamp back. The duo set out once again to the dark castle Fiona is locked away in, guarded by a fire-breathing dragon. But first, Shrek and Donkey had to cross the bridge that was hanging up between the castle and the ground and if you look down, you can see a lake of lava. When they got outside Shrek ordered Donkey to find the stairs because the princess will be in the highest room of the highest tower and Donkey needs stairs to find the princess. Shrek himself went to find and slay the Dragon. While Donkey distracts the dragon, Shrek goes and finds the princess in her room, and drags her out of the castle. After they rescue Donkey, and run off from the castle, leaving it in ruins, when Shrek takes his helmet off, and Fiona is repulsed by the fact that Shrek is an ogre. Shrek didn't appear to care and takes Fiona by force to Farquaad. While they moved to Farquaad Duloc, they met the Merry men where Fiona revealed her Karate skills. After the fight Fiona noticed an arrow in Shrek's butt and gave Donkey an order to find red flowers with blue thorns just to get rid of him. Fiona got the arrow and later they continued their adventure. They later camp, and while Fiona sleeps in a cave, Shrek and Donkey sleep outside and start talking. It is then revealed that Shrek doesn't like being hated by humans and confides in Donkey that they always stereotype him as being a monster. So he just stays away from others in the safety of his swamp. Throughout the rest of the trip back to Farquaad, Fiona warms up to Shrek and Donkey and Shrek begins to fall in love with Fiona. However, when bringing her a flower, Shrek overhears Fiona talking to Donkey about how no one could love an ugly monster. Shrek thinks she's talking about him, and enraged and hurt, he goes and brings Farquaad and his knights to take her to his castle. After that, Shrek is angry at Donkey and starts a fight with him. Shrek then gets his swamp back and he is by himself once again. However, Shrek is still not happy, so he apologizes to Donkey and he convinces Shrek to get Fiona back. They take Dragon (whom Donkey started a relationship with) to Lord Farquaad's palace. Shrek crashes their wedding and confides in Fiona that he loves her. At first, Fiona tells him that he's too late and then starts to kiss Farquaad. However, the sun begins to go down, and Fiona transforms into an ogre too, surprising Shrek. However, Farquaad is disgusted with her now and has her and Shrek arrested. As the guards grab them, Donkey and Dragon burst through the stain glass windows of the church and the Dragon eats Farquaad, thus killing him.
Fiona is still unsure about herself, but Shrek tells Fiona he still thinks she's beautiful, and they get married. The story ends with Shrek and Fiona's wedding, going off in an onion carriage on their way to their honeymoon.
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