Lucian regarded her gravely, before entering her conscious mind with his. It would be strange for her if he didn't restrain himself, a sort of merging of consciousnesses, and it could very well disturb how she perceived certain things. It had occurred before, and in those times it had, Lucian had been able to essentially puppet those he'd melded with, simply because of his superior mental capabilities. He didn't wish such a thing on Zira.
What he did was show her firsthand what it was like, for half an hour, to mess with Brys's stimuli and make him believe only what Lucian wanted him to believe. Lucian had to craft a painstakingly real world, adjust Brys' perception of time, make him truly believe everything he felt and saw was really happening. He had rooted through Brys' dark thoughts, pushing them to the surface and whispering his fears in the back of his mind. He'd paralyzed Brys in reality, to keep him from flailing in his cell and inflicting real damage. And he had to do all this while remaining aware that only thirty minutes of real time were passing; while staying calm and collected as Brys' fear and pain washed over him in powerful waves. He'd had to enact the beating himself, momentarily inserting himself into this mental simulation, and then forcibly retreating, whilst trying to keep it from falling apart.
He showed Zira this as if she were doing it herself, although it was little more than watching his actions through her own eyes like she had done to him. The only difference was that she would feel it as well. It took a full thirty minutes to convey it all, the sensory overload and the complex false reality he had maintained, and while she was under he was awake, assuring people that her limp form was indeed fine. She hadn't passed out, or fallen ill, but was indeed alright. Only after exactly thirty-one minutes did he release her mind, hoping she wouldn't respond too negatively to the experience.