The “escape the corset” movement (ETC-M) is a declaration that actively reflects the voices of Korean women in fourth-wave feminism and spread through social media. This movement emerged as a fashion style against social prejudice and inequality through the lens of feminism and sparked the launch of the “escape the corset” fashion (ETC-F) brand. Feminism, which discusses the conditions of women in our society, is inevitably related to sustainability. It is time to examine the much-neglected social inclusion of sustainable development goals, by examining the declarations that women express through fashion. This study intends to lay down the foundation for in-depth research into ETC-M by understanding the historical background of Korean feminism, the basis of ETC-M. Furthermore, this study aims to analyze ETC-M as a phenomenon that has grown in social media and understand the characteristics and significance of the resulting fashion style. An analysis of the characteristics of ETC-F formed through social media engagement shows that it has developed a range of special items, styles, and looks. ETC-F marked an opportunity to raise awareness about the discriminatory practices in women’s fashion and formed an anti-fashion solidarity among non-mainstream women. In addition to the development of fashion products, ETC-F is leading the development of fashion content that competes with mainstream lifestyle, culture, and entertainment industries. This study offers not only an opportunity to examine the role and meaning of ETC-F from an industrial and cultural perspective, but also implications for the practical consideration of a sustainable society based on inclusion and diversity.