If you haven't yet read
doumeki's fanfiction, then you must take a few moments to read through the few I've posted here, at the very least. She writes Kakei and Saiga perfectly--manipulative, crafty, perverse, and a touch affectionate. Rikuo and Kazahaya get an equally well done treatment with Rikuo's leering and sexual commentary at an all time high and Kazahaya's straightforward and naive ways landing the both of them in sticky situations.
Keeping Warm: It all starts when Kakei sends them to pick something up from someone named ‘Yuuko-san.’
Walking on the Small Man: Rikuo and Kazahaya find a .... leprechaun. That's right. Just stop complaining, okay, and go read it. You'll be sad you didn't think of the idea first.
Psy[chotic] Phone Tag: The readers are lucky enough to listen in on various answering machines and the messages that they contain. One of the funniest damn things I've ever read.