Tosaka

is an ornithologist who works in the services of Konohagakure.

Personality
Tosaka is a very eccentric man, who shows great passion and effort in his work, even climbing up a tree return a nest with its young. He feels the best way to understand something is to apply all five senses to it, even licking the most crude of things.

Appearance
Tosaka is a fairly tall man of light complexion and pale-green eyes. He has silver hair that is chin-length with short bangs over his eyes. He wears a beige bodysuit with a long orange shirt over it and brown gloves along with brown sandals.

Abilities
While apparently not a shinobi, he was requested to join a ninja team on an investigative mission due to his extensive bird knowledge.

Jūgo Arc
When word reached Konohagakure about birds randomly attacking a village, Tosaka was requested to work alongside Team 7 and Team 15. Along the way, Tosaka would continuously analyse any evidence of birds in the area, at times grossing out some of his allies. Upon arriving, the group was attacked by strange-looking birds. At the village, they learned that many people attacked by the mutated birds quickly became sick and were covered in Cursed Seals. The villagers also found an unconscious Jūgo, who was recognised by Sarada and Mitsuki. When the man awoke and was questioned, one the sick villagers went on a feral rampage and attacked Tosaka until he was suddenly drawn to Jūgo.

Tosaka aided Konohamaru moving around after his fight with Jūgo. They followed Team 7 until they found a passed out Jūgo with an injection device by his hand. Tosaka examined him to compare his condition with the birds' affliction, and commented on finding the natural habitat of an endangered bird species. Jūgo woke up just in time to protect them from another bird attack, curing it of its cursed seal before leaving. Back at the village, he corrected Wasabi when she brought up the possibility of Konohamaru contracting Jūgo's cursed seal through his injuries, his analysis from Jūgo's blood sample revealing his cursed seal and the birds' were different. When Mitsuki confirmed the device they found was from Orochimaru's research, Tosaka added it was a powerful tranquilliser, having licked it. Konohamaru tasked Tosaka with helping Team 7 monitor Jūgo and look out for more of the tranquilliser. Tosaka was touched by Jūgo's effort to cure the birds despite the strain it caused him. After Jūgo relented in letting them help, and explained how to determine if a bird was infected even before they turned violent, Tosaka suggested that finding the source of the very territorial birds could help them figure out where the cursed seal came from. Later, Tosaka and the others discussed the lack of progress in their investigation, and wondered if something else was happening.

As the group continue to work in tandem over the next couple days, treating Jūgo while he treated the birds, Jūgo began building an immunity to the injections from such regular usage. Ultimately, he underwent another episode. With all the remaining injections mysteriously disappearing, Jūgo began rampaging on the village. Before anyone was harmed, the researchers from the Land of Rivers arrived and knocked him out with tranquilizers. The villagers revealed that they were spying on the Konoha team, as were the researchers. Once learning that they were hiding the truth about Jūgo, the villagers became furious at the Konoha team and wanted them to leave. When it was revealed that Wasabi Izuno and Namida Suzumeno were infected by curse seals, Tosaka was allowed to stay behind as his expertise still proved vital.