Atsui

is a shinobi from Kumogakure.

Personality
In stark contrast to his sister Samui, Atsui has a rather hot-headed and spirited attitude, which is evident even in battle. He prefers attacking his enemies head on, leaving him entirely devoid of any support at times. He has a tendency of saying the word and admits that he has created a substantial amount of "hot-shot" catchphrases.

Appearance
He has shoulder-length, light coloured hair, worn in an asymmetrical bowl cut style. His typical attire consists of a sleeveless version of the standard Kumogakure uniform, along with the village's respective flak jacket. He also has bandages on his forearms, shin guards and the kanji for tattooed on his left shoulder.

Abilities
Like many other Kumogakure shinobi, Atsui is extremely proficient in the usage of swords, often incorporating a long white katana into his fighting style. When this blade is utilized in conjunction with his Fire Release techniques, through the application of Chakra Flow, he is capable of incinerating a significant quantity of opponents in a single instant.

Shinobi World War Arc
Atsui along with his sister were assigned to the First Division of the Allied Shinobi Forces during the Fourth Shinobi World War. When Darui confronts the resurrected Kinkaku and Ginkaku, Atsui and his sister provide assistance. Attacked almost immediately by numerous White Zetsu, he incinerates them before charging towards the opposing brothers.

Both he and Samui are hit by the Kōkinjō, resulting in their being drawn from their bodies. With their respective word souls subsequently severed and absorbed, the siblings are placed under a combination curse and sealing technique, where if they utter the word they've used most in their lives, they'll be imprisoned for eternity. Although Samui advises that he not speak, Kinkaku's attack prompts Atsui to say "hot", causing him to be sucked into the gourd. Darui promises to find a way to release him. The gourd with Atsui and Samui inside was later taken by Tobi in order to seal the portion of the Nine-Tails' chakra that is within Ginkaku who was also absorbed into the gourd.

Trivia

 * means "hot" in Japanese (in reference to temperature), in contrast to Samui's name which means "cold".

Quotes

 * (To Darui and Samui) "They look like nasty weapons, but in the end they're just tools! Our techniques have soul, they're too hot for these guys to handle!"