later when you leave and return, you will find a pink crystal golem which is past where the hydra was in the water (be careful walking there because you can fall into the deep water portion and die if you are not watching where you step!) kill that pink crystal golem and a girl will pop out. Don't kill the girl! she will talk to you and sell you spells after you re-summon her through her 'sign' which will appear after you talk to her the first time on the shoreline opposite from the cave where you fought the pinky golem.
Her outfit appears back in the cove after you reload your save after summoning her. This is the best reward, the Antiquated Skirt is unreasonably good, having better defense than things that weigh 4 times as much (beats Havel and Smough in everything but Fire and Poise at +5). --- You can't make an omelette without crushing dozens of eggs beneath your steel boot and then publicly disemboweling the chickens that laid them as a warning.
I too beat the hydra, climbed up there, and got completely pwned by the super bush-men. Really startled me since I destroyed many of those things in the earlier part of the forest; those ones up there seem to have 3x the hp and hit for twice as much damage. And there are like two of them attacking you the moment you walk in there. Brutal. I decided to just go elsewhere. :roll: (I was SL 27)