What are Climbing Crescents as used in The Broken Eye

Question

I am currently reading The Broken Eye by Brent Weeks. In one of the chapters the character Teia has to steal something from a tower. She uses something called climbing crescents to help her achieve this goal.

"Mercifully, she had plenty of the climbing crescents. She wasn't going to have to make it a stretch to reach each one."

_{The Broken Eye - Chapter 72}

I haven't been able to find any reference to these other than the mention in this book.

They are obviously some kind of piton to help her climb.

BUT

Are these real life objects (ignoring the magical Luxin they use) used by climbers either today or in the past or something made up specifically by Brent Weeks?

Answer 1

He made them up

So I asked the man himself. And he confirmed that he made them up. Though he didn't rule out that something might exist with some seriously strong adhesive, as fuzzyboots suggested in their answer.

And here is the link to the tweet

Answer 2

TL;DR: They were made up by the author to provide a convenient way for the protagonist to ascend and descend sheer surfaces while leaving no trace of her route.

More detail

Based on the context (needing a certain amount to cover the distance comfortable) and the need to reach them, I think they are like pitons, wedges attached to the surface that can be used as handholds and footholds.

The Blood Mirror has a bit more description:

Each climbing crescent had a string dangling from it. Pull that string in a big circle around your crescent, and the string cut it off the wall. Each time you removed it, you lost adhesive luxin, but the crescents could be reused.

That suggests that the crescents are not actually pushed into the surface, but stuck to it. Quick Google Book searches have references to her placing her hands and feet on them, and always needing to remove the crescents back off from the surface to ensure that all traces of her travel are removed.

I do not believe we currently have a real-world version of this. Pitons, bolts, camming devices, hexes, and nuts are used somewhat similarly, but require either cracks or driving the holds into the surface, and pitons are the only ones that really provide an actual foothold or handhold rather than something to anchor a rope to. The closest parallel in terms of providing handholds and footholds are climbing holds, which are permanent bolted-in installations. Frankly, we just don't have the magic glue (luxin) that attaches so firmly and so quickly, but is removed so easily, although the various "Gecko" adhesive strategies are getting close. The next closest would be climbing cups, but they're not meant to be left in place, and only work on extremely smooth surfaces like glass.