Gate to the Ever After

In addition, she had on board one member of that species who walked behind the stars. Its name was ninety-one syllables long, but it answered to Nephauree. The physical form it presented to her was
an illusion: a thin wavering line of smoke-shadow, standing three times her height. Of its true form, she knew nothing. Once she'd made the error of demanding that she see it as it actually was, and the experience had had almost made her ready to stab out her own eyes.
- Abarat