Fan Casting Rosalyn in Calvin and Hobbes

Rosalyn, the last of the significant recurring characters to appear, is a high school senior and the only babysitter able to tolerate Calvin's antics. Rosalyn is perhaps the only character in the strip whom Calvin really fears (other than Moe, the school bully). Introduced in an early strip, Watterson found her ferocity and intimidation of Calvin surprising, and he brought her back periodically in increasingly elaborate story-lines. Watterson described their relationship as "one-dimensional", although in her final appearance Rosalyn agrees to play a game of Calvinball, and in so doing, becoming the only character in the strip, other than Hobbes, to truly engage with Calvin on his own terms.