William pulled his hand back immediately, more of a startled reaction to Gabe actually physically touching him than shame at being caught out with the evidence of failed experimentation marring his skin. The last time Gabe had done that had been in the hospital wing, arms wrapped around William's torso, cradling him back against his chest...but that hadn't been voluntary at all, had it? That had been, to use Healer Bryar's professionally blunt words, mental rape, and not Gabe at all.
He tugged his sleeves down and folded his hands in his lap, out of sight behind the desk. "I was testing some of our hypotheses," he told Gabe, voice miraculously steady. "Nothing dangerous. I'm certainly nowhere near close to a viable solution, and I can't brew a potion of the level of complexity this would require." Not without help and destroying Gabe's workroom, anyway. Again. Something told him Gabe would not be anywhere near as forgiving a second time. Particularly not since things between them had changed considerably since then.
He pushed those thoughts away and focused on what Gabe had been saying about African magical traditions. The most widespread scarification practices often involved cutting or branding, and neither of those sounded like especially attractive options. Although.
"Is there a way to burn ink directly into someone's skin?" he mused, rubbing a thumb slowly over his bruised wrist. "Perhaps by using a potion with an acidic nature, or something more permanent, magically speaking? Fiendfyre?"
That was not an experiment he would easily volunteer for, however. He knew well enough what Fiendfyre could do on the loose, and he didn't have much faith in it being successfully harnessed. Particularly not in attempting to bind it directly into his blood.