Yvonne is the love interest, later girlfriend of Toxie in Toxic Crusader. She was voiced by Kath Soucie.
Yvonne is often playing the accordion and singing soprano so high that it would break things, but Toxie is too polite to criticize her about it.
One time the show literally broke the fourth wall in the form of Yvonne's singing causing the viewer's TV to break (in the form of animated broken glass) and Toxie apologizing to the viewer and saying the Toxic Crusaders will come by to buy them new TV sets.
She is based on Toxie's blind girlfriend Sarah from the movies, yet Yvonne is nearsighted.
Unlike most other depictions of Toxie's love interest, Yvonne is only legally blind and can see if wearing glasses.