Mikkakan no Koufuku

Kusunoki used to believe he was destined for great things. Ostracized as a child, he held on to a belief that a good life was waiting for him in the years ahead. Now approaching the age of twenty, he's a completely mediocre college student with no motivation, no dreams, and no money. After learning he can sell his remaining years—and just how little they're worth—he chooses to divest himself of all but his last three months. Has Kusunoki truly destroyed his last chance to find happiness...or has he somehow found it? (Source: Yen Press)

Mikkakan no Koufuku began as a web novel posted on the message board 2channel under the title Jumyou wo Kaitotte Moratta. Ichinen ni Tsuki, Ichimanen de. (寿命を買い取ってもらった。一年につき、一万円で。). An expanded and modified version of the series was published in print by ASCII Media Works on December 25, 2013 under its Media Works Bunko label. The series was published in English as Three Days of Happiness by Yen Press under the Yen On imprint on October 20, 2020, in French by Editions Akata under the Young Novel imprint on March 28, 2019, in German by Egmont Manga under the Roman imprint on October 7, 2020, and in Spanish by Norma Editorial on May 14, 2021.