Jackson is the former captain, now co-captain, of the Beacon Hills lacrosse team. Like Lydia, he is a popular student. Jackson has a competitive and aggressive nature, which shows through hostility towards people who best him. The show implies that he wants to make others proud of him. Despite his abrasive personality, Jackson is shown to care about his friends and dislikes hurting them. Jackson is insecure about his adoption and the fact that he does not know his real parents, leading him to be unable to see his adopted parents as his true mom and dad. His birth mother had died on June 14 while pregnant, meaning he had been pulled out of his dead mother's womb.
Derek gives Jackson the bite but his body rejects it and Jackson instead becomes the Kanima, a murderous shapeshifting creature that is a weapon of vengeance. The Kanima seeks a master who wishes to exact revenge on others to control it, revealing that as the Kanima, Jackson's every move is controlled by someone else. Unlike werewolves, who retain their memories despite transformations, Jackson does not know that he is the Kanima, nor does the Kanima side of him know that it is Jackson. Peter Hale reveals that Jackson became the Kanima because he is an orphan, meaning he lacks an identity, just as the Kanima lacks one. However, Jackson can be saved by a person with whom he shared a true bond. In Jackson's case, this person is shown to be Lydia. Through Lydia's selflessness in the finale, Jackson heals and finally becomes a werewolf.
[Not Jackson, don't own Teen Wolf, muse & mun 18+]