Eyghon's mark was permanent, of course, but there had been other symbols drawn on his body before that, temporary marks for some ritual or another they were trying, things that required less commitment than summoning the Sleepwalker had. Ethan had been the one to draw them, in general; Ethan was far more gifted with a brush than he'd been, and could be counted on to get the symbols right first time.
When it was just the two of them, he couldn't be counted on to draw the runes somewhere as innocent as a forearm, but Ripper hadn't ever minded, because really, it was all one thing to them--the magic and the power and the sex and the constant search for the thrill that wouldn't let them down, all wrapped into one, and there was no need to separate them.
Those sigils had washed away, of course; soap and hot water and they were gone as though they'd never even existed in the first place.
Years later, he'd wondered why those had been the markings that he could still feel, when he almost never gave a second glance to the tattoo on his forearm.