Atsui

is a shinobi from Kumogakure and brother of Samui. He was assigned to the First Division in the Fourth Great Shinobi World War.

Personality
In stark contrast to his sister, Atsui possesses a rather hot-headed and spirited attitude, which is evident even in the heat of battle. This impulsive temperament often results in serious repercussions, especially during confrontations, where he is likely to impetuously charge ahead others, leaving him entirely devoid of any support. He has a tendency of saying the word and admits that he has created a substantial amount of "hot-shot" catchphrases.

Appearance
He has medium length light-colored 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
When Darui confronts the resurrected Kinkaku and Ginkaku, Atsui and his sister provide assistance. Attacked almost immediately by numerous White Zetsu, he incinerates the Zetsu before charging towards the opposing brothers. Both he and Samui are hit by the Kōkinjō, resulting in their souls being drawn from their bodies through their mouths. With their respective 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 Ginkaku's crimson 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!"