This article examines the short-lived Marvel comic Misty (1985–1986), created by feminist cartoonist Trina Robbins, as a case study in how comics can invite and depend on reader participation. We draw on an archival collection of over 1,000 fan letters and fashion designs submitted to Misty, along with recent communications with former readers, to explore how children and young adults influenced both the published comic and its surrounding culture. We argue that readers’ contributions – ranging from clothing designs to story ideas – constituted a form of activism: they challenged corporate publishing practices, promoted new story directions, and built local fan communities. Highlighting the recent memories of Misty’s reader contributors, we show how engaging in the comic’s participatory culture could, in turn, have lasting effects on readers, shaping their confidence, career paths, and creative philosophies. By reframing Misty’s collective participatory culture as activism and placing it in conversation with readers’ personal memories, this study contributes to scholarship on comics, fandom, and memory: even small acts of reader engagement can transform both cultural texts and individual lives.