From Portals of Phereon Wiki
You can sometimes find Castalia researching all sorts of stuff like different species here.
Actions[ | ]
- Help (1h or 30m)
- As long as your relationship with Castalia is at 21 or above, once a day, you can either spend 1 hour helping her by milking centaur cocks, which can help you unlock various types of centaur based species forms and increase your hands and mouth skills or (not available to Creation) spend 30 minutes drinking a mysterious vial and receiving a blowjob from Castalia, this will either increase your cock size or your cum amount permanently.