Background
Kisame is a former member of Kirigakure's Seven Swordsmen of the Mist (霧の忍刀七人衆, Kiri no Shinobigatana Shichinin Shū), an ever-changing group of ninja that wield particularly large weapons in battle. While in Kirigakure, Kisame is known to have formed a connection to Suigetsu Hozuki and his brother. His former country, the Land of Water, now seeks him out for plotting to overthrow its government and being involved in numerous assassinations. Kisame would later join Akatsuki and be partnered with Itachi Uchiha.

Appearance
Kisame has a distinctive shark-like appearance, complete with pale blue skin, small white eyes, gill-like facial structures, and sharp triangular teeth. Even his name, Kisame (鬼鮫), means "Demon Shark", while his last name, Hoshigaki means star ghoul. Hoshi means star and gaki means ghoul.

Personality

Kisame is rather battle-loving, enjoying having to fight others, though, when forced to leave a fight, states to his opponent(s) that they "don't know how lucky they are." Like other characters who have trained to be one of the Seven Swordsmen, Kisame enjoys mutilating his opponents, as seen when he suggests cutting off Naruto Uzumaki's legs to make him easier to carry.
Kisame is also one of the few members of Akatsuki he gets along well with his partner. Kisame has a slight loyalty to Itachi, willing to take any comands he gives without complaints and constantly looks out for his well-being. Although Kisame does have his pride, he acknowledges Itachi as the stronger of their duo.

Weapon & Abilities

Kisame's weapon is called Samehada (鮫肌; Literally meaning "shark skin"), a sentient, scale-covered sword that shaves off skin instead of cutting. Samehada is also capable of absorbing chakra, but requires Kisame's chakra to do it. Only Kisame is allowed to wield Samehada; if anyone besides him tries to pick it up, spikes protrude from its handle and it returns to Kisame's side.
Kisame has also been known to display astonishing speed and incredible physical strength. He uses water-based jutsu in combination with his powerful physical attacks. His shark-like qualities carry over to the type of techniques he uses in battle, as he often shapes bodies of water into the forms of sharks that proceed to attack opponents. If there is no water source where he happens to be fighting, Kisame can use Water Release: Exploding Water Shockwave to create a lake's worth of water to be used for attacks. Kisame is also noted to have a particularly large amounts of chakra in his reserves; even when he fights at 30% power in one instance his chakra supply is compared to that of a Nine-Tailed Demon Fox-enhanced Naruto Uzumaki.

Part I

Return of Itachi arc

Kisame is first introduced alongside Itachi during a mission to kidnap Naruto Uzumaki. After he and Itachi gain attention due to their unusual clothing, Kisame and Itachi face off against Asuma Sarutobi and Kurenai Yuhi, two Konoha Jonin. The two Jonin stand little chance, however, and are almost immediately defeated. The arrival of Kakashi Hatake, however, prevents the two's deaths. While Itachi fights Kakashi, Kisame waits patiently for Itachi's victory. After Itachi orders Kisame to kidnap Kakashi and kill Asuma and Kurenai, Might Guy arrives and kicks an attacking Kisame in the face, to which Kisame resents to this day. Following Guy's arrival, Itachi orders Kisame to retreat, not wanting to start a war.
Itachi and Kisame then continue hunting Naruto, finding him under the protection of Jiraiya, who neither are risking fighting. After Itachi hypnotises a beautiful woman to seduce Jiraiya and leave Naruto alone, Kisame and Itachi confront Naruto in a hotel hallway. Kisame considers removing Naruto's legs so he can't run away, though Sasuke Uchiha, Itachi's younger brother, shows up in time to distract the two from Naruto. When Naruto attempts to fight, Kisame uses Samehada to absorb all of Naruto's chakra. Kisame then attempts cutting off Naruto's arms so he won't be capable of weaving hand signs, though Jiraiya defends Naruto with relative ease. Following Jiraiya's initiation of the Toad Mouth Technique, Kisame and Itachi leave without kidnapping Naruto.

Sasuke Retrieval arc

While not making a physical appearance, Kisame's hologram does appear during an Akatsuki meeting.

Part II

Rescue Gaara arc

Kisame gets a Part II introduction in the form of a clone created from the body of a Sunagakure council to distract Team Guy, which attempts to rescue Gaara from Akatsuki's clutches. Kisame is later revealed to have chosen to fight them as revenge for Guy kicking his face. While Guy is able to withstand Kisame's attacks, the others are incapable of doing so and eventually get locked within Kisame's Water Prison Technique. Guy then takes no time to attempt saving his comrades, eventually defeating Kisame's clone with an Eight Gate technique.

Current arc

Kisame successfully manages to capture the Four-Tailed beast, his assigned Tailed beast, around the same time Team Snake is formed. During the following Akatsuki meeting to seal the Four-Tails, Kisame and Itachi are informed of Team Snake's formation with Sasuke as its leader. Kisame is later told by Itachi to stand guard outside the former Uchiha clan headquarters and to let in only Sasuke. After Sasuke leaves the rest of Team Snake, Suigetsu (another ex-member of the mist's seven swordsmen) starts a fight with Kisame, wanting to claim Samehada as his own.