In episode 8, Shinichi uses a fanbook "Cure Kosette Punishment" to distract the palace guards about 15 minutes into the episode. It's clearly a doujin fanbook which is based on Precure (or Outbreak Company's equivalent). But I can't tell if this book is entirely fictional, or is based off a similar real-world work. Is there any similar real-world doujin fanbook on which this one was based?
Cure Kosette is a parody of Cure Rosetta, who was a PreCure in DokiDoki PreCure which was airing at the time. Ironically, it'd make more sense for Cure Rosetta to do the punishing, as she more or less is an ojou-sama who beat up some high school age delinquents when she was still in grade school. As for the doujin itself, unfortunately Cure Rosetta/Yotsuba Alice (civillian form) does not have all too many doujin in which she takes the leading role. She is one of my favorite cures by far, the only doujin that seem similar to this one seem to have rather poor art. Dokidoki PreCuring A__ce Hen is the closest thing I've found, which is technically a CG set, not a doujin. So as far as I can tell, there is no real world equivalent... even though there should be, lol.
Anyway, good luck in your endeavors and all that.
