Across the world, Костягин (Костягин , Kostiagin ) is an extremely rare unknown gender first name. Much more frequently, Костягин is the last name as well as the forename.
Kostyahin
Амир, Юрий, Тимур, Роман, Михаил, Андрей, Виктор, Руслан, Алексей, Дмитрий, Николай, Василий, Геннадий, Владимир, and Владислав
, Kostiagin 
) is an extremely rare unknown gender first name. Much more frequently, Костягин is the last name as well as the forename.