Well, of course we can discuss the issue in the Prefect meeting, Ms. Patil, but you might try speaking with the Professor directly. Of course, this may vary from instructor to instructor, but I have always personally found that Professor Slughorn to be most open to hearing from his students, and he might simply change your work partner in response to a simple, polite request, particularly if he agrees with you that another pairing might be best for all concerned.

Obviously, he'd be more likely to listen to you than to me, since he considers me an obnoxious minger at best.