Sasuke devotes years of his life to avenging their family by killing Itachi. He became cold, unmoved and uninterested in what others do/think of him, choosing to keep to himself. He stopped using honourifics, something rude in Japanese language. His only goal in life is to take revenge for his clan's deaths by any means, even if it meant acquiring power that wasn't his own. Sasuke can quickly evaluate others’ abilities, completely disregarding those weaker than him. His birthday is July 23rd.