Four is sporting a jet black hair, wears an all-black outfit, which is convenient when blending in the shadows. He is also shown wearing silver earrings in both ears.
Night Form: His augmented form shows red lines and eyes.
Four is described as a tsundere character. His entire demeanor is cold and doesn’t seem to care about the others. He is known to be precise on his job and is not prone to mistakes. He is independent and always says his opinion and prefers action than words which contradicts operative Nine on his diplomatic tendencies. A perfectionist with a mentor-like attitude, Four is always seen lecturing Zero and Seven, Phantom Alpha’s rookies, whenever they commit mistakes on missions. Though he might look unconcerned, Four is a very reliable teammate and a man of his words.
Four met Seven before she became an operative. He became less cold towards her as soon as it was implied that she'll join PHASe. He is also one of the operatives that spend the most time with her. Even though he might seem distant sometimes, he and Seven get along quite well. They can easily have conversations even with Four's short answers and can manage to have a good time occasionally. And being a part of his team, he'll do anything to keep her safe.
Four may seem to be harsh and unforgiving whenever Zero commits mistakes but the real reason behind it is because he wants him to develop into his full potential, which shows that he truly cares for him.
Four has shown to have absolute deep respect for the leader of Phantom Alpha. He trusts him beyond doubt and will not hesitate to follow his orders during missions.
Four has an overall a good relationship with Six and even though he can be a bit annoyed by his teasing, the two shows respect with one another. Six seems to be the only one to have this level of friendship with Four.
Four doesn't have a good relationship with Dr.Park for an unknown reason yet to be revealed.
Four holds a strong dislike towards the Magician. Aside from her being from KAIROS they both have strong personalities and are very competitive which add fuel to the fire. They have the same speciality (guns) and often encounter one another on missions (directly or indirectly).
In the game
- Four is considered as the Best Gun in Olympia in rivalry with Magician of Blue Wings. There's an "unofficial" score being kept between the both of them where they constantly try to outdo each other. Neither one stays in the 1st place for long because of it.
- Four uses the sniper rifle L115A3 AWM (Arctic Warfare Magnum) chambered in .338 Lapua Magnum (effective firing range: 1.203yd = 1.100m) or in .338 Lapua Magnum (effective firing range: 1.531yd = 1.400m).
- Four is proficient in most types of combat.
- Four has a sweet tooth, he's even aware of a secret menu at the cafeteria that allows someone to eat, according to himself, the best dessert that one will ever have in a lifetime.
- The shipping name for Four and Magician is Mag4.