Natsume is a extremely intelligent, to the point of being considered a genius, and despite this, ditches class frequently. Hated and feared by a lot of students at the academy because of his dangerous Alice and cold attitude. Due to the isolation he feels from most of his classmates and hatred many student feel about him he is often bullied even though he comes to ignore it, although the class he is a part of holds him in very high regard and often follows his orders.
He is thoroughly unhappy with the school and is always suspicious of the intentions of adults because he believes that they use their power over the younger students to hurt and abuse. He is involved in top-secret missions for the Academy which are shady and haven't quite been explained in the story yet, although he often returns injured.
He is paired up as Mikan's partner in class by the their mostly-absent class teacher, Narumi. Although at first he rebels strongly against this duty, he later accepts it and begins to enjoy Mikan's company, along with the company of his classmates and finds himself getting friendlier as the series progresses, although he never quite loses his dangerous edge and temper.
He possesses the fire Alice. It is revealed early on that since Natsume has such a powerful Alice, it causes a lot of stress on his body to use and shortens his lifespan immensely. He had been showing the symptoms of a life shortening Alice for a year before the start of the series and had been progressing quickly due to the constant use of his abilities for missions for the Academy. Because of this, he can be seen quite a few times through the manga coughing blood or even going unconcious.
He has a close group of friends, which at first is only Ruka, the only person at the Academy who understands his reasons for being there and originally agreed to come to the Academy because of Natsume. Later, though, he grows deeply fond of Mikan and finds himself trying to protect her from the dark side of the Academy. He gets extremely jealous whenever if Narumi, Tsubasa or any other male character gets too close with her, something that is often used against him by the older boys for teasing. He's often seen kicking the older guys shins, holding Mikan back from hugging others or burning the tips of Mikan's hair to get her attention again.
He is the only Special Star in the Elementary Division, thus entitling him to a lot of luxurious things that he never really gets to take advantage of.
