Information about Saix

Source: https://www.youtube.com/watch?v=zkulWp6OXyA

This is Saix, a character from the Kingdom Hearts games series.
Even though he looks like a human, he is a Nobody. According to the games, the loss of someone's heart results to the creation of a dark creature called a Heartless. These creatures attack people who have hearts to steal them from them, and try to invade the heart of every World and thus, destroying them. If the character of the person who became a Heartless is strong enough, another creature is being created called a Nobody.
A Nobody is a creature who has not a heart, but it has soul, logic and a body. According to the instruction booklet of Kingdom Hearts 2, they are "between light and dark". He is a member of Organization 13, a team constisted of Nobodies who aim for the creation of a Kingdom Hearts, a place where the freed from the Heartless hearts go. They believe that with this way, they will gain a heart for themselves.The scope of Saix is the same.
As a person, he is very remote, serious, quiet, cold (PlayscopeDS, 2014) and he does not show his feelings while speaking, regularly.
However, he is very strong, having the element of the "Moon" and fighting with a "weapon" called "Claymore" (PlayscopeDS, 2014).
His past is not very clear. While he had a heart he was Isa, and had a friend called Lea. These two people, seemed to want to be students of Ansem the Wise, a man who investigates the hearts. However, they were thrown out of the man's castle. It is unknown if they managed to do what they wanted to.
His friend became also a Nobody and a member of Organization 13, with the name Axel.
Despite the fact that Saix is a loyal member, he wants to "find" "clues" "about" the "true agenda" of his leader (Everglow, 2013). Additionally, he does not seem to like Axel's new friends.

Sources: https://www.youtube.com/watch?v=6t2xMSBvloo
https://www.youtube.com/watch?v=zkulWp6OXyA
https://www.youtube.com/watch?v=g2q-9TjLH6c&t=187s