Caleb is depicted as the childhood friend of the Player. He was adopted alongside the Player by Josephine, who he refers to as "Gran," though they have no blood relation. As a child, he had a love of planes. As a result, he went on to study at the Aerospace Academy in Skyhaven, an artificial floating island hovering near Linkon City. Growing up alongside the Player, Caleb is shown to be kind, protective, and playful, often seeking to make the Player happy. Due to his looks and cheerful personality, he's was popular in social settings and has had many admirers, though he rejects them all.
Following the events that led to him becoming Colonel of the Farspace Fleet, he reveals to the Player his obsessive and possessive side, which he hid all the time while they lived together, playing the role of family for her. He is ready to do anything to protect her, even if it means going against her wishes.
As a Colonel, he is cold, calculated, and highly respected amongst the Farspace Fleet, though he is shown to receive some backlash from other high ranking personnel. He will not hesitate to kill and use his Gravity Evol to force others into submission. He is comfortable threatening others with death, especially when it comes to the Player's safety or threats to his position in the Fleet.