Aokiji

Kuzan, better known by his former alias Aokiji, was one of the three Marine admirals. He was nominated by Sengoku for the position of fleet admiral. However, after losing the position to Akainu, he resigned from the Marines.
Kuzan is a very laid back man, showing no shock or surprise from almost anything. His lack of interest and lazy justice (as he describes his motto himself) let others often believe he can not possibly be a marine of such a high ranking. However, if he deems a situation worthy, he will take action, as shown when he created a passage to another island for a few injured castaways at Long Ring Long Land.
He seems to be the kindest of the three admirals, helping Tonjit at Long Ring Land to cross the ocean with the power of his Devil Fruit and even letting Nico Robin escape the Buster Call on Ohara. He seems to dislike the Shichibukai, or at least Crocodile; he said that the only reason he did not kill Luffy was that Luffy had defeated Crocodile.
In contrast to his fellow admiral Sakazuki, Kuzan has a sense of honour, as he keeps his word to not attack the Straw Hats after accepting a one-on-one fight with Luffy. Kuzan’s moral stance is unknown, but it is likely that he follows Moral Justice. He is disgusted by Sakazuki’s brutal actions in dealing with situations (such as the Ohara Incident), calling him a fool. While he may follow Moral Justice, he does understand the position his ranking puts him in, as he does not hesitate to do what is necessary for the needs of the Marines, as shown when he freezes Jaguar D. Saul after the Ohara incident, and attacked Luffy and Whitebeard during the Marineford War.
Aokiji was a faithful follower of the World Government. He always tried to obey orders but sometimes found his own ideals in opposition to his orders. Even as he followed his orders, he would sometimes exhibit a sense of mercy and honor that other World Government officials did not. Like many characters in One Piece (for example, Jaguar D. Saul and Smoker), after witnessing the senseless murder of many innocent people, Aokiji may have come to realise how low these events have sunk the World Government.
His relaxed demeanour while performing the more macabre of his duties is similar to that of Borsalino, making him one of the more complicated characters in the series. Despite not really wanting the position of fleet admiral, he was even more opposed to Sakazuki getting the position, and fought his fellow admiral rather than letting him take it. After being defeated, Kuzan chose to resign from the Marines rather than stay under Akainu’s command.