I don't get the riddle and I don't even know if I should be ashamed that I don't. I get the innuendo though.
Yes, yes, the answer is "money-changing machine", right? Chen...What's with this letdown!Fufu, I'm looking forward to it.A-a-are you sure I can say it? Heey, are you absolutely sure? Cheeeeeeee-As expected from Ran-sama!Yukari-sama, I've got a riddle."Do that and you can make kids," is what?Riddle"Make a wrinkled thing straight, and put it in the hole".