Nox likely jumped right to demon because of his most recent experiences. He was worried there could be an uprising of sorts just getting started. The man in the stairwell had been scared, to a degree. He felt someone was after him, another shadow demon, and he'd originally suspected Hesper. But Hesper wasn't hurting anyone, and Nox didn't think the stranger had either. Which meant a hunter was still on the prowl. Maybe hunting had turned to outright psychotic outbursts of murderous rage.
His attention returned to their witness when she mentioned she wanted to go home. He nodded a second after Hale and watched as his partner handed the woman a card with both their numbers on it. "Those are our cell phones. Call at any hour, work does and so can you." He looked the woman directly in the eyes, "We'll catch him," he reassured her, as well as himself at the same time.
Moving toward his partner, Nox muttered, "It's gonna be a long night. The conversation can wait. I wanna get this guy."