Born in 1968, Wills attended the University of Washington earning a degree in history of science, technology and medicine. While at the University, Wills was elected UW student body president. After college, Wills worked as an aide to King County Executive Ron Sims. She was elected to City Council in 1999, defeating Charlie Chong, to serve a four-year term. She was defeated by David Della in 2004.

During her tenure on Council, Wills was chair of the Energy and Environmental Policy Committee and vice-chair for the Housing, Human Services, Education, and Civil Rights Committee, and the Transportation Committee. She was passionate about environmental issues, and worked towards establishing standards for "green" buildings, as well as air and water quality issues. The Energy Committee also gave Wills one of her most difficult jobs, that of managing the electric utility during a volatile energy market. Under Wills, council approved four rate increases to start paying off debt. Wills was also involved in the search for a new superintendent for City Light.

Perhaps the major challenge Wills faced during her term was questionable campaign contributions from strip club owner Frank Colacurcio and land use zoning at his club "Rick's." She repaid the contributions and a fine but the issue may have cost her re-election. Wills also worked on third-party billing for water and sewer. The proposed legislation was an attempt to regulate how landlords bill their tenants for utilities.

She was married during her tenure on City Council, to Kobi Yamada in 2002. In 2005, Wills became Executive Director of The First Tee of Great Seattle, part of a World Golf Foundation initiative dedicated to providing young people of all backgrounds an opportunity to develop through golf and character education.