The April 2021 issue of Square Enix’s Gangan Joker magazine has announced that Matcha Hazuki’s One Week Friends manga will get a sequel manga titled One Week Friends Afterwards in the magazine’s next issue on April 22, 2021.
Yen Press published the original One Week Friends manga in English, and describes the story as:
Yuuki Hase desperately wants to be friends with Kaori Fujimiya, the girl in class who seems to always be alone. Just when he thinks they’ve hit it off, she tells him her secret: Every week, her memories reset. Yuuki resolves to befriend her as many times as it takes, but is he prepared for how much it will hurt to be one week friends?