In Naoki Urasawa's Monster, there were "recitals" held with children at the Red Rose Mansion. Did they ever explain what these "recitals" really were? Were the children reenacting the events of some of the picture books? I have watched the whole series and I never quite understood what a "recital" actually was.
So after speaking with a friend... The "recitals" were merely sessions by Bonaparte in which his picture books were read to the children in order to brainwash them. This was all part of his experiment.
According to Wikipedia:
Bonaparta is held responsible for the eugenics experiment leading to the birth of the Liebert twins, and author of the storybooks used to indoctrinate the children of Rose Mansion (notably The Nameless Monster, from which Johan took his name and his mode of operation). Other books include The Big Eyed Man and the Big Mouthed Man, The God of Peace and The Quiet Village. His stories are full of metaphor and symbolism, often with monsters as important characters. Most also promote the idea that human nature contains the ability to become good or evil, although his works tend to denounce humanity rather than uplift it.