Nikolai Plisetsky

Nikolai is the grandfather of Yuri Plisetsky.

Nikolai has been very invested in Yuri's figure skating since Yuri was a child, attending his competitions in place of his mother. Yuri adores his grandfather deeply, thinking of him when the he needed to understand unconditional love for his short program.

Nikolai is a quiet and kind gentleman. He does not speak much, preferring to listen to his grandson talk. He takes up a genuinely loving grandparent role, picking Yuri up from the Sheremetyevo International Airport, making Pirozhki for his grandson, and learns about what Yuri likes. Nikolai makes an effort to attend competitions in Moscow that Yuri competes in to show his support, showing his dedication towards Yuri.

(Source: Yuri!!! On Ice Wikia)