The Citadel: Prophecies

V: 651 - Regarding Patchface

Melisandre’s face darkened. "That creature is dangerous. Many a time I have glimpsed him in my flames. Sometimes there are skulls about him, and his lips are red with blood."

The skulls, featured in others of Melisandre's visions regarding Jon Snow, appear to relate to death. The lips red with blood, on the other hand, seem hard to interpret.