One Week Friends (Japanese: 一週間フレンズ。, Hepburn: Isshūkan Furenzu.) is a manga series by Matcha Hazuki. It was serialized in Square Enix‘s Gangan Joker magazine between January 21, 2012 and January 22, 2015. It was first published as a one-shot manga in the magazine’s September 2011 issue. The series has since been collected in seven tankōbon volumes. An anime television series adaptation by Brain’s Base aired between April 6 and June 22, 2014. Sentai Filmworks licensed the rights to the show in North America and by Madman Entertainment in Australia and New Zealand. A live-action film of the same name was released in February 2017.

Plot

High schooler Yūki Hase notices that his beautiful classmate Kaori Fujimiya is always alone and seemingly has no friends. After approaching her and becoming better acquainted, Kaori reveals that every Monday she loses all memory of her friends. Despite learning this, Yūki endeavors to befriend her anew every week.

Manga

One Week Friends began as a one-shot manga by Matcha Hazuki and was first published in Gangan Joker‘s September 2011 issue. A full serialization later followed in Square Enix‘s Gangan Joker from January 21, 2012. After spanning three years, the series came to an end in the February 2015 issue of Gangan Joker which was published in Japan on January 22, 2015. Despite the end of the serialization, a special chapter will later be included in the magazine’s May 2015 issue when it is published on April 22, 2015. The chapters was collected into a total of seven tankōbon volumes, the first of which was released on June 22, 2012. The final volume was released on April 22, 2015. During their Sakura-Con 2017 panel, Yen Press announced their license to the manga.

On March 22, 2021, the April 2021 issue of Gangan Joker revealed that a sequel manga titled Sono Ato no Isshūkan Friends would begin serialization in the next issue.

Reception

Carl Kimlinger of Anime News Network gave One Week Friends an overall B+ rating. He wrote that the premise can push its dramatic moments a little too far and almost nothing happens throughout the first half of the series. Regardless, Kimlinger praised the plot’s character development, saying that it saves the first half with its progression through little events; he added that the dramatic scenes are nicely underplayed to help viewers care for the characters. Kimlinger wrote that Brain’s Base and director Tarou Iwasaki provide the series with a style that’s perfect, calling the minimalist backgrounds evocative with the right mood and the character animations superb, saying “that makes the show what it is: a sleeper delight, plain and simple.” Fellow ANN editor Gabriella Ekens praised the show for being “emotionally intelligent” with its showcase of Yūki’s character growth and for being “beautifully realized” with its “faux-water color style” illustrating Kaori’s progression and recovery from amnesia, concluding that: “One Week Friends is slice of life at its best. Gentle, atmospheric, and emotionally resonant, it’s the perfect comfort food for an afternoon in. It might be quiet, but you won’t forget about it any time soon.” Conversely, Allen Moody from THEM Anime Reviews criticized the “blandness and predictability” of the premise and its characters, singling out Saki for being “annoying on several levels”, but commended the show’s overall “inoffensiveness” and felt that both Shōgo and Kaori’s mom Shiho were the only “genuinely good” people throughout the series.

The manga has had over 1 million copies printed in Japan.

One Week Friends
Cover of Isshūkan Friends volume 1 by Square Enix
一週間フレンズ。 (Isshūkan Furenzu.)
Genre	Romance
Manga
Written by	Matcha Hazuki
Published by	Square Enix
English publisher	NA Yen Press
Magazine	Gangan Joker
Demographic	Shōnen
Original run	January 21, 2012 – January 22, 2015
Volumes	7 (List of volumes)
Anime television series
Directed by	Tarou Iwasaki
Written by	Shōtarō Suga
Music by	Nobuko Toda
Studio	Brain’s Base
Licensed by	AUS Madman Entertainment NA Sentai Filmworks
Original network	Tokyo MX, MBS, TVA, BS11, AT-X
Original run	April 6, 2014 – June 22, 2014
Episodes	12 + 12 Special episodes included in the DVD / Blu-ray of the series. (List of episodes)
Manga
Sono Ato no Isshūkan Friends
Written by	Matcha Hazuki
Published by	Square Enix
Magazine	Gangan Joker
Demographic	Shōnen
Original run	April 22, 2021 – present
Live-action film
One Week Friends (film)