It’s not mind-reading,’ she said. ‘Not even an empathy link. Just … a temporary wave of exhaustion. Primal emotions. Your pain washes over me. I take on some of your burden.’
Nico’s expression became guarded. He twisted the silver skull ring on his finger, the same way Reyna did with her silver ring when she was thinking. Sharing a habit with the son of Hades made her uneasy.

Rick Riordan