I thought it was sort of interesting and had never come up much before until
Joker's post, so I'm going to essay a little bit here.
There's tons of villains in Patalliro, but thus far I'm the only one who has really played a character who has been a villain in the series and I think there's a bit of an interesting take to be had on their codes.
Patalliro is a generally lighthearted (but not always) series. Even the villains will have their lighthearted moments. It's also a series that lives off jokes and puns. Particularly bad puns (which are often considered "bad" jokes in English, and probably also considered laughably bad in Patalliro).
This also means that anytime a villain brings up a question there's almost always some form of witty answer that will solve it. There's even trouble-making characters in the series that can manipulate the world around them using bad puns.
I never thought too much about this until it came to answering Joker's question. Maraich, without a doubt, would be playing by the rules the villains on his own world have. That means if someone poses a questions there's probably a bad pun to be made out of it.
It also generally means the wittier you are the more likely you can cut them off with a good answer.
Simple guessing games are likely his style. If there's no wit, bad puns, references or possible jokes to be made out of it he probably won't like it. In Joker's case, with the answer, he had a sudden realization that it was basically nothing but a random number. In that case there wasn't any amount of wit that could come up with a right answer the first time. I highly doubt Maraich would care for guessing games that essentially couldn't be won unless you had good luck.
Having something random, something that couldn't be figured out, almost came off as cheating to him.
It's a very strange sort of code that I think would be embedded in most the characters of Patalliro. I doubt Maraich even realized he had it before he came face to face with a villain that didn't.
The difference in how the different villains acted almost came out naturally, and I thought it was an interesting note.