Despite coming from a chaebol family, Carter Han has had a fairly tough time growing up. Despite having what would be considered an extraordinarily privileged background, Carter Han had a fairly lonely and isolated childhood. He had no friends growing up and was shunned by all his family members except for his grandfather who loved him very much.
Due to the constant attacks by his family, Carter Han became a very cautious person and does not trust people easily.
Two years later, Carter Han has been fighting in the real world constantly which made him much tougher. He far more confident in his ability and looks forward to facing difficult challenges ahead. He acts cold and aloof which led to him being called a Tsundere by Wolf, acting cold on the outside but in fact caring about others. He worries about his friends safety and puts himself in front of danger in order to protect them. He feels guilt for his weakness that he believes took away all that was precious to him ( Helen, Roy Han, and Hardcore Leveling Warrior), so he desire to atone for these sins by getting stronger and getting revenge onto giga
During season 1, Carter Han was very insecure about his height and did not like it when people made comments about it. This is no longer the case as he had a massive growth spurt in both the real world and the game.