20. Saotome Mary's Life Plan Book
"Ah, Saotome-san!"
When Jabami Yumeko saw that it was Saotome Mary, there wasn't even a trace of the oppressive aura she had exuded during their gambling match two days ago.
Completely ignoring the unwillingness written all over Saotome's face, Yumeko cheerfully grabbed her hand and wrapped her in her ample, soft embrace, like they were the best of sisters.
"I came to talk to you two!" Mary blushed furiously and struggled to break free from Yumeko's grasp.
Fidgeting shyly, she twirled a strand of her hair around her finger and couldn't bring herself to look them in the eye. "I came to give you a warning."
"Warning? Did something happen?"
"You beat Sumeragi Itsuki yesterday, right?"
"Yes! Did Saotome-san see it too? That triple memory game was so much fun. I really want to try it with Hachiman-kun sometime."
"Hachiman, let's do quadruple memory game next time!"
Yumeko excitedly placed both her hands over Hikigaya's, causing Mary's eyebrow to twitch in irritation.
Tch— It's only been two days, since when did their relationship get this cozy?
"Yumeko, calm down and let her finish what she's saying."
Hikigaya, expressionless and trying his best to stay composed, pulled his hand back. His mind was completely blank—even mentally reciting prime numbers couldn't restore his peace.
Mary looked deadly serious. "She's in the student council, you guys know that, right?"
"The student council doesn't take it lightly when someone challenges their authority and gets away with it. And sure enough, someone approached me last night. They told me to bring you two to a casino run by one of the council's officers."
"Casino..." Hikigaya's interest was piqued.
On one hand, the forbidden nature of the word made it feel alien and mysterious. On the other, he'd also been curious about the student council's inner structure.
Suzui had mentioned before that Sumeragi Itsuki got into the council through a large donation—essentially buying her way in—and was considered one of the weakest members.
But her triple memory game… Honestly, most people couldn't win against that. Even if someone figured out the marked cards, memorizing the entire deck layout in under two minutes was a different beast entirely.
It was just Itsuki's bad luck to go up against Yumeko and him.
If Mary had joined that same game, she probably would've lost badly too—and might've ended up having her fingernails taken.
So then, what level of skill did those council members running the casinos possess?
He spoke up, "Who was it?"
"Nishinotouin Yuriko, the president of the Traditional Culture Research Club," Mary said the name with a dry throat, feeling as if she were facing a deadly enemy. She instinctively glanced around, then wiped the cold sweat forming on her forehead. "That woman… she's incredibly scary. I haven't gambled against her myself, but I know about her methods."
"Her gambling is known as the 'Cheat-Proof Game.'"
"Cheat-proof?"
Hikigaya and Jabami Yumeko exchanged a glance, seeing the spark of interest in each other's eyes.
"How so?" Yumeko, once again shifting into her elegant debutante mode, straightened her back, folded her hands in front of her abdomen, and listened intently to Mary Saotome's explanation.
"The game is called 'Life and Death'. It's essentially betting on which hole a sword-shaped piece will fall into. But what makes it special is this—besides guessing the correct hole, you also have to predict the direction the blade points in. If the blade faces upward, you can claim 30 times your wager from your opponent. If not, you lose 30 times instead."
Hikigaya Hachiman rubbed his chin. The rules didn't sound particularly strange.
Perhaps noticing the disinterest on their faces, Mary emphasized again, "The key point is—she's never lost. Not even once."
"I once watched her gamble. She always wins in the most critical rounds and completely cleans her opponents out. But… I couldn't figure out how Nishinotouin was winning. The dealer's hands were clean..."
"Maybe... she really does have some kind of gambling luck."
Having finished, Mary let out a breath and studied their expressions—only to find no sign of hesitation.
"No need to think about it. In a setup like that, it's definitely cheating," Hikigaya scoffed. "Can't find the trick? A 'cheat-proof' game? That just means the technique is good enough not to be easily detected."
"From your description, this is a game based entirely on probability. And yet she wins every single big-stake round? The only logical explanation is cheating. 'Gambling luck'? That kind of vague nonsense doesn't exist."
"But didn't you say it was luck yesterday, Hikigaya-kun?" Yumeko chimed in softly, followed by a helpless sigh.
"Saotome-san, why did you come tell us this, anyway? We did make you lose ten million yen the other day," Hikigaya said, glancing sidelong at her.
'If this is just an attempt to repay debt with gossip about how scary the student council is, then sorry—this doesn't cut it.'
Hikigaya Hachiman was a meticulous and self-serving person, with not a shred of romantic pity.
What he followed was the principle of equivalent exchange.
"I…" Mary's throat moved as she swallowed. She glanced at Hikigaya unconsciously and said in a whisper, "I want to ask for your help, Hikigaya-kun. To gamble with me."
"Huh? Gamble with you?" Hikigaya asked, genuinely surprised. That was a scenario he hadn't considered...
"I'm sorry, but I don't like gambling. And I'm even less interested in gambling for someone who owes me ten million yen."
"No, that's not it!" Mary quickly corrected, nervously twisting the ends of her hair. "I want to challenge a casino. I just want Hikigaya-kun to back me up. I'll participate in the game myself!"
"Help me keep an eye on whether the other side is cheating. And if they are, let me know. Regardless of whether they cheat or not, win or lose, I'll pay you an extra ten million yen! If I win, I'll split the casino's profits with you fifty-fifty!"
"Oh? Ten million?" Hikigaya raised an eyebrow. "That just so happens to be the amount you owe me, Saotome-san."
"I can't come up with that much right now. But… even if I lose, I swear I'll pay you back," she said, her tone dimming. Her beautiful face was half-hidden beneath her bangs.
"In the end, you're trying to get something for nothing. Saying you don't need my help, but you're really betting on my curiosity, on the chance I won't just stand by and watch, that I'll point out the cheating when it happens. Maybe even help you cheat in return."
Hikigaya pulled a thermos from his backpack and took a sip of goji berry water to moisten his throat. "Nice speech. But I refu—"
SLAP—
Mary slammed a sheet of paper heavily onto the table. It was densely packed with text and clauses.
"Oh? What's this…"
"My life plan," she said. "I've already mortgaged my entire life to the student council."
Her amber eyes flickered with dark flames—the fire of a will that had staked everything, now burning fiercely with resolve.
"So… will you help me, Hikigaya-kun?"