Marrianne is a studen from Mt. Pleasant High School mentioned in Beth Ann Nelson's Address Book. Considering that Beth Ann Nelson was not very popular and never had a "best friend", Marrianne was the closest thing to a best friend Beth ever had. Marrianne's phone number was 555-9547 but at some point before 1980 she moved and her new number was 555-9441.
Marrianne wa caught once forging a note for Beth to get out of lessons while Beth would help her in Physics. She liked a friend of Adam Carlson and did not understand why her interest was shifted from Adam to Merrick Campbell.
Beth and Marrianne used to correspond by writing in a notebook during boring lessons.