Gilgamesh is a tyrant because he kills men and takes advantage of women in his kingdom. He is too smart and too strong, and no one can be his equal.
Gilgamesh is very strong. He is arrogant, and walks around looking down on people.
Gilgamesh seems to take whatever he wants. Neither men nor women are safe from him. He takes the boys in duel and has his way with the women.
No son is left with his father, for Gilgamesh takes them all; and is this the king, the shepherd of his people? His lust leaves no virgin to her lover, neither the warrior's daughter nor the wife of the noble. (I)
As a result, his people fear him. He seems too strong for them to defend against, so they ask for help from the gods. The gods hear their plea and decide to make a companion for Gilgamesh that will be just as strong as he is.
‘You made him, O Aruru; now create his equal; let it be as like him as his own reflection, his second self; stormy heart for stormy heart. Let them contend together and leave Uruk in quiet. (I)
After Enkidu comes, Gilgamesh calms down. By the end of the story he has turned into an excellent king.