Hachiman Hikigaya, pondering the superficiality of marriage's portrayal as a blissful union, is thrust into the world of matrimony when the Volunteer Service Club is assigned a project to promote marriage in a local magazine. Tasked with a topic they have little familiarity with, Hachiman and his clubmates, including their advisor Shizuka Hiratsuka, scramble to grasp the essence of marriage within a tight deadline. With unconventional methods on the table, the group dives headfirst into unraveling the mysteries of this sacred bond.