What is the Death Note a-Kira one-shot?

Death Note: a-Kira, by Ohba and Obata, ran in Jump Square on February 4, 2020, fourteen years after the series ended. Ryuk, bored again, brings the notebook back to Earth and hands it to Minoru Tanaka, the highest scoring student in Japan, a boy with Light's intellect and the opposite instinct. Minoru returns the notebook on the spot, tells Ryuk to bring it back in two years, when he is old enough to hold a bank account, and spends the interval planning the only use of a Death Note nobody had tried: he auctions it. Announced to the world under the name a-Kira, the notebook is offered to the governments of the Earth, and the bidding war that follows, watched by a Near now serving as L and building shinigami tracking technology, is the story's chess match.

The winning bid comes from the President of the United States, drawn as the then sitting president, at a price set to pay every Japanese citizen under sixty a life changing sum. Minoru's plan is flawless except for the one player nobody can audit: the King of Death, offended or amused, adds a new rule to the book mid game. A Death Note may not be bought or sold; the buyer can never use it, and the rule reaches backward to the seller. The president quietly returns the unusable notebook. Minoru, his memory surrendered and his fortune already in his account, is met by Ryuk at the bank, and the one-shot closes with Ryuk writing a name beside Light Yagami's, longing for a human who would play longer.

a-Kira was collected, with the earlier 2008 one-shot C-Kira and other short works, in Death Note: Short Stories (2021), the volume to look for. Identification is simple and worth doing: the one-shot's magazine appearance is Jump Square, not Weekly Shonen Jump, and its hero is Minoru, not Light. Any listing that blurs those two facts is a listing that has not read its own book.