Underdark Voyeurs

When the players set up camp for the evening if someone falls asleep on watch, they awake to dozens of footprints around them, their friends, and the campsite. Nobody was hurt, but everyone wakes up with small pebbles placed over their eyes.
The next time someone falls asleep on watch one random player wakes up with a small creature lifting the player’s lip to try to steal their teeth while they are asleep. Upon waking up, they see dozens of these creatures sneaking up to the rest of the party. The small creatures shriek, and swarm the party.