Hyouka - Volume 03 - The Kudryavka Sequence - Welcome to KANYA FESTA! (1)

Chitanda was the only one who didn't get it.
Watching her squeeze her green bean paste bread to smithereens, I explained
to her, "It is as you have wondered, he wouldn't have targeted the clubs
randomly. It's all following a pattern, and a very simple one at that. The only
reason we didn't realize it earlier was because the order in which we were
told which clubs were targeted was mixed up. So, assuming the Film Club
was targeted, we have: The A Capella Club, Go Club, Fortune Telling
Association, Film Club, and The Cooking Club."
"Ah!"
Chitanda covered her mouth.
"The gojuuon sequence!"
Meanwhile, Satoshi was doing the rounds, calling someone on his cell phone.
"...Yes, just want to know if you've got something stolen... No, it's not me!
Honest! ...Hmm? A water gun? I see, thanks."
He hung up the call as the three of us looked on.
Then he said, "It was the Gardening Club. One of their water guns was stolen
while they were away from the room."
"Water gun? Why would the Gardening Club have water guns?"
A sensible question from Ibara, which I answered at once.
"They were making sweet potatoes, so they needed to prepare water to put
out the fire, and they decided to use water guns because it looked cool that
way."
"O-Oreki! How on earth did you know that!?"
Well, I'm sorry that I have amazing levels of perception. But actually, it was
thanks to the Glock 17 that I had obtained earlier on. Ibara continued to
mutter.