Oh, and I forgot to present this clever detail that Ruthyruth discovered (all credits to her):
"It seems there is some kind of legal requirement in Japan for scripted dramas to explicitly declare that they are "works of fiction".
Typically at the very end of a broadcast a disclaimer will appear in the lower right corner of the screen.
Top left is an example from another show
このドラマはフィクションです。(kono dorama wa fikushon desu) "This drama is a work of fiction."
In the Kotaro series there are no "work of fiction" disclaimers at the end of the episodes!
Rather, they've casually blended them into the context of each show.
In episode 1 in the very first shot starting at about 4 seconds, please look at the piece of paper taped to the apartment entrance.
In episode 2 keep an eye open at approximately 05:07 as Karino's boss thumbs through the drawings.
In episode 3 at approximately 04:03 when Karino and Kotaro are leaving the school yard the camera pans down to the ground.
It's kind of like how Alfred Hitchcock would make a clever appearance in each of his movies! Seriously cool and clever!"