Blades Quest 5: Ashlander Informant
Get some more "orders" from Caius. He'll tell you that you need some info from an Ashlander informant named Hassour Zainsubani, and gives you 100 gold to get something to please Hassour.
Go to Ald-Ruhn (by Silt Strider, if you'd like) and enter the Ald Kkar Inn. Hassour is in the room just below the bar level — go up to the bar and then down the stairs through the floor on that level). Talk to Hassour, and ask him about "gift-giving customs". Ask about thoughtful gifts. If you have a high speechcraft skill, he'll follow the "thought is what counts" ideal and be pleased with this. If not, he'll ask you to find him some poetry.
If you need the poetry, there's a local bookstore with several books of song that will do nicely, including Ashlanders Hymns.
Ask Hassouur about the Ashlanders and he'll give you the notes for Caius. He'll promote you to "Finder". At this point, the story begins to progress as Caius reveals some information about the package you delivered from Seyda Neen.