There are many different masks that Natsume Takashi has. There is the mask he shows his relatives. There is the mask he shows his classmates. There is the mask that he shows to family. All show Natsume, but they have never contained Takashi, never showing who he really is. In the past, before his parents died, Takashi was a sweet and wholly innocent little boy. He did what every little boy did: play and have fun. He talked to his dad and to all his little friends, be human or not. Takashi could see spirits, just like his grandmother, Natsume Reiko. But when his father passed away and Takashi was whisked off to be with relative to relative, he would change. He would learn to don these varying masks of his, to hide himself in a world where he thought he wasn't welcome in.
Takashi at the age of five was brought to the first relative. They dealt with him. Since Takashi was just a little boy, he acted as he always had. He talked to his relatives and talked to all his little friends, human or not. But this is where he learned from his first mistake. Where his father had always smiled and nodded at his little friends, Takashi's relatives were not understanding. They at first thought he was speaking to an imaginary friend, something all children will do sometime in their life. But when Takashi would speak and act and have strange things happen to him, they realized something was wrong. It was like something bad was stalking Takashi, something that lurked and brought misfortune. By the time he was six years old, Natsume Takashi donned his first mask: the mask that he shows to his relatives.
Natsume at the age of ten was brought to the seventh relative. They ignored him, barely gave him the necessities to live, barely acknowledged his education. Natsume didn't and shouldn't exist, at least in their eyes. At school, he was bullied and ostracized for being an orphan. And when he started talking to air, to nothing, he was treated like a monster. Everyone was scared of him, the teachers, the other students. Even the parents of the other children were terrified. Who was this little boy who talked to air? Natsume learned that everything he did was wrong; everything about him was wrong. By the time he was eleven years old, Natsume Takashi donned his second mask: the mask that he shows to his classmates.
Natsume at the age of fifteen was chosen by the twelfth family. From the hospital bed that he landed on after a tussle with a spirit, Natsume met the Fujiwara couple. A kindly older pair with no children of their own, they welcomed Natsume with gentle arms. Fujiwara Touko made him boxed lunches every morning and a hearty dinner every night. She took care of him when he was sick and welcomed every single friend he has and probably will ever bring home. Fujiwara Shigeru was a steadfast rock to lean on, a constant Natsume could rely on. He didn't treat Natsume like a small child. He treated Natsume like the young adult he was, with respect and support and so much unsaid love. The two loved Natsume dearly, as he loved them just as much. Because of that, Natsume Takashi donned his third and final mask: the mask he shows to his family.
Unlike the little boy he was all those years ago, Takashi was not naive. He knew the cruelties of humanity, the pain they could inflict at the slightest whisper, the slightest touch. He had all but given up hope, when the Fujiwara's came into his life. Takashi knew, they were the ones that would keep him, that would cherish him. So, he hid behind his mask. If the Fujiwara's found out about his ability to see and talk to spirits, they might (in all likelihood they would never) send him away just like all the others. At the same time, Takashi swore to himself. He needed to protect them. If they knew about his ability, they would worry every time he came home with mud stains on his knees and scrapes over his body. They would be in pain and he didn't want that.
Natsume Takashi has changed over the years. From the innocently sweet little boy all those years ago, to the gentle wary young adult he is now, Takashi still wore his masks. Just, now they all weren't for hiding himself for his own safety. They were also for the people he wished to protect, the people he loved.