Instructions
Talk to Lady Grey in Bowerstone North. She asks you to bring her a gift but does not specify what she wants. You cannot get this conversation until you beat the Arena quest and see the cut scene between Lady Grey and Thunder.
Buy a Black Rose from the item shop in Bowerstone North.
Return to Lady Grey. She tells you to buy a house.
Purchase any house in town. The house in Bowerstone South is the cheapest available, costing only 4100 gold.
Return to Lady Grey. She tells you that she lost her necklace and asks for you to find it for her.
Go to Oakvale. Dig between the two boats on the shore to find her necklace.
Return to Lady Grey. She now demands you fight Thunder in a duel.
Go to Headsmen Hill to find Thunder.
Defeat Thunder in combat. He is only an average melee fighter with above-average health. This fight should not pose a major problem.
Return to Lady Grey to marry her.