To say Tristan was wary was an understatement. He wasn't sure what to make of people acknowledging his existence outside of things like handing over and picking up cloaks, telling him where to plant what, scheduled appointments with his therapist and probation worker, and his immediate family (which included Titus and Fluffy). For the most part, he'd begun to think he was a ghost, and he'd come to terms with that. He was a ghost trapped in a shell, and he was alright with that. He was a ghost in a shell, and he found he could live with that. He didn't have to do a lot of thinking as a ghost in a shell, and he certainly didn't have to do a lot of interacting.
And then people responded to him.
And if he were honest, he didn't know what to do.
He knew even less of what to do when Cho invited him for tea. But he'd accepted her offer, warily, because, ultimately, whatever instincts about polite society had been drilled into him as a child had known what to do.
Tristan put on simple black robes, thinking this wasn't a fancy occasion, and he wanted to be comfortable. People also didn't seem to pay much attention to background colours and neutrals like greys and blacks and browns. He didn't fuss with his hair much, save for brushing it, tucking his behind his ears a bit to keep it out of his face. And his face... Well, he definitely used a few well placed charms to conceal any dark circles or thinning of his person to prevent any strange looks or concerned questions. He didn't know that Cho would comment on his looks at all (not even his hair, which had been growing out for years and was still growing out. Maybe he'd cut it one day), but he didn't want to take that risk and be stuck swatting at awkward questions and potential sidelong looks. He was fine enough, healthy enough, thank you, and that's how he looked. And any tiredness was to be expected from working nights, after all
He used the Floot Network to arrive at the Leaky Cauldron, not wanting to bother with Apparating. (Although he had his licence, it wasn't always the most pleasant experience, and he thought this day had the potential for all sorts of unpleasant experiences. He didn't need to add one more. Not that Cho herself was unpleasant; just everything in general could add up to be that way.) He stepped out of the fireplace, brushed himself off, and looked around, not sure from where she might be headed.
It didn't take long to find her, and he approached, stopping a proper, polite, safe distance from her. "Hello," he said, with a light voice and smile.