Nyau is a member of Esdeath's bodyguard "The Three Beasts". Despite his playful personality and innocent looks, he was by far the most sadistic member of the group with his hobby of collecting human faces.

Like the other members he was charged by Esdeath to lure out Night Raid while getting rid of the Prime Minister's political enemies in secret. He battled with Tatsumi and Bulat aboard the cruise ship "Ryuusen" where he caused all the passengers to fall asleep by using his Teigu, Scream.