Kurogane is one of the main protagonists of the manga/anime series Tsubasa: Reservoir Chronicle. He is a ninja from feudal Japan who was sent to meet the Dimensional Witch, Yuuko Ichihara, by the princess of his country, Tomoyo Daidouji, after he became one of Syaoran's companions in his quest to collect Sakura's feathers, along with the mage Fai D. Flowright.
He is voiced by Tetsu Inada in the Japanese version of the anime and Christopher R. Sabat in the English version, the latter of whom also voices Piccolo, Kero-chan (true form), Ayame Sohma and Alex Louis Armstrong.
Kurogane is the tallest member of the group, being a good bit taller than Fai and towering over Syaoran and Sakura. He has spiky black hair and a stern, serious expression.
At the start of the series, Kurogane comes off as absurdly arrogant and self-serving, with all of his goals being for his benefit. Unlike Fai, he had no desire to help Syaoran, stating that he only tagged along with them so that he could get back to his own country. He is a very serious man and is greatly irritated by all the cutesy nicknames Fai gives him. However, Kurogane is also a bit of a hypocrite as there is almost nobody he calls by their real names- Syaoran is 'the kid', Sakura is 'the princess', Fai is 'the mage', Yuuko is 'the witch' and Mokona is 'the meat bun'.
Later on, however, Kurogane shows that he's actually not a bad person, when he starts to help the others in their quest and agrees to train Syaoran in swordplay. While he seems rather irreverent, he is also very loyal, especially to Tomoyo. However abrasive and ruthless Kurogane may seem, he has a compassionate nature and a desire to protect. An example of this would be how he constantly questions Fai on his actions and character, and lets the wizard know that he should stop hanging onto his past and embrace the future with his new companions. Or, Kurogane's own statement that "If someone wants to take away the ones I want to protect, I'll kill them too."
Kurogane is also extremely perceptive, being able to quickly discern Syaoran's fighting ability (along with Syaoran's blind right eye) as well as Fai's true nature and fighting capabilities. He is likely the most experienced fighter in the group and wiser than he appears. While training Syaoran, he teaches him a philosophy that he lives by: a sword is used to cut only when needed and not used to cut anything if it is not necessary.