To free Princess Trueberry from her loveless curse, you'll have to present to her ten people who are in love. To accomplish this, first visit the nymph Athea in the south-west corner of Area A4. This will cause all male party members to fall in love. (Sorry, all-female parties... you'll have to get some male hirelings for this one.) Have these characters talk to Princess Trueberry. She'll somehow "absorb" their love. Now, return to Athea and repeat the above until Princess Trueberry has absorbed love from at least ten characters. This will break the curse and free her. Your reward is half a million experience points!

Also, she'll give you the Alacorn of Icarus. All you need to do to solve Icarus' quest is bring it back to the Shrine of Icarus, a hut in area A2. For completing this quest, you'll get a whopping 2 million experience!