Nitori is a very shy Kappa who lives on the Youkai Mountain and if she is alone and sees a human, she'll run away. She has the power to control water. Along with the other kappa she is very good with technical stuff, as she is an engineer.
Nitori considers herself to be superior to humans and even other youkai, and when she's by herself it's easy to see. However, when among her own circle of friends, she is quite cheerful. As a kappa, she is easily persuaded to leave you alone by a cucumber or two. However, she has a greedy side when it comes to running a stand and is quick to come up with plots to maximize profit.
(Source: Touhou Wikia)