Obito wasn 't all that old when someone finally explained to him why the twist of colors on his wrist grew warm at random times. Whenever he spent time outside of the Uchiha compound it cooled to the same temperature as the rest of his skin usually ' unless he was inside the academy, where it warmed up until it felt like his fingers did after holding a mug of hot chocolate. The one time he had slipped past the gate guards and gotten lost exploring the forest surrounding the village, his mark had cooled until it felt like when he played outside in the winter without any gloves.