Despite Yumeko’s absolute lack of restraint when it comes to gambling, she isn't the most disturbing character in Kakegurui. That title goes to the Head of the Beautification Club, Midari Ikishima. It’s easy to recognize her because she wears an eye patch over her left eye and is usually seen waving a gun around. When she challenges Yumeko to a bet, it’s a very simple one: A game of Russian roulette where instead of shooting yourself, you shoot your opponent with a gun and hope you don’t end up killing them. Although Yumeko finds a way to win without killing anyone, it is still a weird bet to allow at any school.

The first member of the student council that Yumeko faces is Itsuki Sumeragi, who had to pay her way into the Student Council and has the really weird hobby of collecting painted fingernails. Not fake fingernails, but the fingernails of those who lose against her, ripped from their fingers. The game itself is simple: A speed memory flip game with a new deck. But it’s the complicated way to cheat Itsuki came up with—using special thermal ink marks and a heated bag to carry the cards—what makes it memorable; add to the fact that it helps to establish both Yumeko and the school as a place where all bets are allowed, and no bet is too risky or weird.

The first bet in Kakegurui XX shows us how much the stakes have gone up because it's one that literally requires no skill: it's all luck and a lot of courage. The setup, as provided by Erimi Mushibami is very simple: A finger guillotine with about 20 strings tied to it. One of them holds the blade, the others are just decoys. Each player must put their index on it, and then cut one string per turn. Erimi has prepared this as part of her family tradition, torture. She doesn’t really plan to cut her fingers: there is a hidden steel plate that protects her, but she enjoys making her opponents suffer and see them fear the blade and lose.

This is a particularly complex bet created by Yumeko and Terano Totobami, in which each participant—Yumeko, Itsuki, Kaede Manyuda, Ibara Obami, and Miroslava Honebami—must choose between putting money in a personal savings bank or pay a tax that will later be multiplied and divided equally among everyone present. In the end, one of the group can be voted out if it’s discovered that they’re not working with the team, and the one with most coins will win an extra 100 votes for the election. It's both a gamble and a test of wills because they could all win a minimum of 20 votes each if they worked together, or lose it all.

The tower of Doors is a building created by Kirari Momobami for no specific reason, but it ends up being used in a bet between Yumeko and Sayaka Igarashi. Every door requires the answer of a riddle to open, and the only way to win is to get from the fifth floor to the first and back again before your opponent. In that sense, the tower is not a bet, but a race. What makes it weird is what they decide to play for: If Yumeko loses, she won’t gamble again, and if Sayaka loses, she will be treated as a non-person by Kirari, whom Sayaka loves. You can’t get more metaphysical than betting your heart's desire, and that is why the Tower of Doors takes the first place on our list.