There were many things that people did not understand about the Inuzuka clan. Because of this, many considered them to be feral and as animalistic as the dogs they lived along side of. Their wild appearance and rough nature did little to dispel these thoughts. However, Shino Aburame was not most people. He likened the Inuzuka to the Aburame. Both misunderstood by people and both taking on characteristics of their inhuman companions.
But even he did not fully understand the Inuzuka's in his class. Kiba and Shikon, twin brother and sister, both hailed from the Inuzuka clan. Like most of their clan, they were wilder than the average shinobi their age. But Shino knew why. He just did not understand why they did what they did at times. He only had the basic understanding of the Inuzuka; he was not able to decipher what the meanings were behind their gestures, postures and expressions. It was like a foreign code to him. Shino prided himself on being intelligent, more analytical than most of his peers. But these two were a challenge, one he would not be happy until he figured them out.
Kiba was far more impulsive and hotheaded than his sister. He was also simpler to figure out personality wise. Trying to assert his dominance against people who challenged him, he was loud and aggressive, though still physically courteous towards the female population of the class. Something Shino put to him having a sister. One he was fiercely protective of, knocking out any guy who dared to speak out of turn around his twin.
Meanwhile, Shikon was quieter. Her rough nature only coming out in spars and competition, Shikon was more relaxed, following her brothers lead instead, and backing him up during confrontations.
Yes, Shino could figure out their personalities easily. What he had difficulty with was the way they communicated with each other. So he began to study them in silence, observing everything they did. The challenge was harder than what they were learning in class anyway.
