Kakegurui Midari (賭ケグルイ 妄) is a spin-off set before the events of Kakegurui - Compulsive Gambler. It focuses on a new character, Ayame Nureba, and her interactions with Midari Ikishima after she became part of the Student Council and head of the Beautification office. It was originally published by Square Enix and serialized by Manga UP. It was first released on February 21, 2017. The manga is written by Homura Kawamoto and the artist is Yuuichi Hiiragi.
See also: List of Kakegurui Midari Volumes
Midari Ikishima becomes head of the Beautification office and Kirari introduces her to the other Student Council members. Next, a girl named Nureba is seen losing 200,000 Yen against Ootori. Since she is now in debt and can't pay, but Ootori makes a proposal. She knows some companies which look for cute girls to make love with and she plans to sell Nureba there, in order to get back the money. Nureba is absolutely devastated and climbs on a roof to commit suicide. However, Midari comes in to stop her. Nureba doesn't want to change her mind, then Midari proposes that they decide her life by gamble. If Midari wins, she can't commit suicide. She then proceeds to first push Nureba and then lift her up again. Nureba's near-death experience left her in shock and conflicted. Midari explains to her, that she didn't really want to die.
With some new gained hope, Nureba challenges Ootori again. If she wins, she can erase her debt. If she loses, Ootori makes it clear, that she will have to sleep with a stranger. They proceed to play blackjack. Nureba is on the verge of losing, then Midari steps in. She then exposes Ootoris cheating and cancels the game. Instead Midari suggests a new game. They have to use compasses to stab in-between Midaris spread fingers. Out of Ootori and Nureba, whoever gets back and forth more times in a minute, wins. The loser has to pay 10 million. Nureba realizes, that Midari wasn't trying to help her, but only thought about herself. They are hesitant at first, but agree. Ootori is determined to win and gets 14 hits. Now its Nurebas turn. Midari reminds her, that she will have to open her legs to every man if she loses. She taunts Nureba, who nervously starts. She instantly stabs one of Midari's fingers. She is sorry and stops, but Midari screams at her to just die. This makes Nureba snap and she stabs with extreme speed. However, she pierced Midaris fingers a lot. Midari just prompts her to be faster and enjoys the pain. Ootori is terrified, standing next to them.
After one minute, Nureba wins by a big difference. Ootori thought she would lose, after all she hurt a Student Council member. But Midari laughs it off, saying she never stated that as part of the rules. She then asks Nureba if she wants to join the Beautification Council and that she would enjoy her life there. She then asks Nureba, whether she had fun too. Nureba is nervous, when Midari suggests, that they could have even more fun like that. Ootori is freaked out by the two psychos. Nureba can't decide whether she should join, but Midari is persistent. When she is reminded that Midari somewhat saved her life, she eventually agrees. They go to the Beautification center. There they are greeted by the Beautification Vice president, Habakiri. She asks who Nureba is. Midari explains how fun it was, that she got to suffer because of Nureba. But Habakiri announces her disgust against Midari, since she is so masochistic and not serious, since Midari doesn't attend their meetings and hangs out with suspicious girls. Habakiri states, she isn't normal and not worthy of Beautification President. Habakiri doesn't want to let Nureba join. Midari proposes to decide it by gambling, but Habakiri refuses because that's what Midari always does. But then she says that she will leave the presidents seat if Habakiri wins. Now she is intrigued and agrees. Midari gets her girls to bring in the money for Nureba to gamble with. The gamble is established and Habakiri now plays against Nureba with Midari's seat on the line.
- Kakegurui Midari takes place after Kakegurui Twin: in Twin, Midari is shown without an eyepatch.