The 'Keep the Door Open Three Inches' meme originates from the third season of the Netflix series Stranger Things, where Chief Jim Hopper establishes a strict boundary for Eleven and Mike's relationship. While initially played for comedic effect to showcase Hopper's protective fatherhood, the phrase took on a deeply emotional meaning following the season finale's tear-jerking letter. In meme culture, the template is used to represent authoritative rules, the setting of boundaries, or to poke fun at overprotective behavior. It resonates with fans of the show who use the image of Hopper's stern face to enforce humorous 'rules' in various social and fandom contexts.