Kiba had seen Shino undressed countless times-- just like Kurenai had, though not Hinata, who blushed and averted her gaze, despite Kiba's frequent refusal to put clothes back on. Whether it was training or bathing on extended missions, Shino always stripped down calmly and efficiently, just like he did everything, like it wasn't any issue, as though he didn't normally go around wrapped in thirty pounds of clothing.
Shino didn't ever seem self-conscious when he was naked-- his body was certainly less beat up than Kiba's, even than Hinata's, and his face, while not distinctive, was nice-- but he did hold himself still with worry. His face as he pulled himself out of the river would be pensive, his wet sun-sheen shoulders tight; but it was the erratic playful movement in the water that made him frown, not Kiba's gaze; and Kiba could only figure that Shino's skin just wasn't enough protection for everything inside him that he needed to protect. He was a hive. He was driven to add layers, to bring the inside further in.
Kiba, meanwhile, was driven to remove layers. He pushed the corners of the unbuttoned jacket up around Shino's shoulders, then over and onto the floor. He slipped his fingertips beneath the hem of Shino's black undershirt, and long thin hands caught his wrists. Kiba's fingers curled into the flesh of Shino's stomach. As much as it was Shino's instinct to protect the hive, it was Kiba's instinct to nudge it with his nose and to gnaw at it.
Kiba growled and leaned forward.
He wanted to roll it around on the floor till it broke.