Reiki Yuki (雪レイキ, Yuki Reiki) was a shinobi of Kirigakure's Yuki clan. He is the father of Kiyomi Yuki, Raiden Yuki, and Mizuko Yuki and the husband of Mizu Yuki. Reiki grew up during the times of the "Bloody Mist" and had to endure the harsh ways of the academy. He lived with his two sisters. He was also forced to go into hiding because how much hate those with kekkei genkai were receiving. Though Reiki disliked being forced into hiding, he was entirely loyal to Kiri and did not move, but developed his abilities in the shadows. Eventually, a woman named Mizu left to go to Kiri for a mission and met Reiki and the two eventually married after Mizu moved to Kirigakure permanently, eventually having two kids: Kiyomi and Raiden and Mizu was left pregnant with a third child.
Reiki left to go travel one day, yet unfortunately did not return and died young. This left Mizu as a single mother and caused her to value peace over almost all things since fighting took the life of her husband. Reiki decided he wanted to travel a part of the world, and was seen saying goodbye to his family and telling his wife and a five-year-old Kiyomi and Raiden that he would return. He mentioned that there was no need to worry and with that, he left.
Sadly, Reiki fought an Iwagakure shinobi who proved to be too much to handle, and Reiki was killed in combat. In his last moments, he tearfully stated that he was sorry to Mizu and his children and stated how much he loved them. After that, he succumbed to his wounds and died on the battlefield.