Marisi is the solution to the medium anagram clue: I AM SIR. She will present the player with a Challenge scroll which reads "How many districts form the city of Great Kourend?", the answer to which is 5.
Marisi sells basic farming tools, which can be accessed by talking to her and asking Can you sell me something? It is not an actual shop and it has no set stock; each item has to be bought individually through the dialogue.