A Noble Burden
Monte asks you to gather special Giant's Skulls from some nobles in the City of Light.
Here you see the target's houses. They can be done in any order.
The closest is the Neville house. So go ahead and enter. Ignore Benedict Neville by the stairs and go directly for his wife, Thea Neville, upstairs. Mention the skull to her and she says that she doesn't like the skull. So she will let you take it and she will handle her husband.
The next is the Talbot household. Galvin Talbot wants to sell it to you. If you have high dexterity of 9, you can take it down from 1000 to 500. Or kill him. If you give him 1000 though, he mentions that he can finally help some people with the money you gave.
The next house is the Ferrers. Speak to her and like the others, you can kill her or help her with a problem. Her son ran away so offer your help to her.
Go upstairs to find Sorean's diary. Read it and find out that he ran off to the Salty Keg.
Go to the Salty Keg and find Sorean. Get him to come home to his mother.
After getting her son back, Dimia Ferrers gives you the item you are searching for.
The last noble house is the de Clare household. However, unlike the others, the only option you have is to kill him since he is a very bad person. So end him and take the Giant's Skull. Don't forget to loot the place since a lot of highly priced items will be available to get in his house.
Get back to Monte and give him the skulls to complete the quest.