Sunlight burns your flesh and causes it to ignite.
Drawback
Direct sunlight burns you for 2d6 points of damage per round. On a failed Fortitude save (DC 15 + the number of rounds you are exposed to direct sunlight), your catch fire, burning for 1d6 fire damage per round. The fire can be extinguished as a move action, but only after you are no longer in the sun.
In addition, you are susceptible to spells and effects with special rules for creatures harmed by sunlight.