A dryad who lives in her grove south of Tatzlford with her satyr friend Falchos. When she was in danger from a scythe tree, the players killed the evil tree and saved her. As a reward, she spent a night with Stan, though she does not seem to have any memories of it.
The group unknowingly led the trolls from the southern fortress directly to Tiressia’s grove. Unable to defend against them, she perished in the fight and her Oathtree was cut down.