I have been re-watching Mawaru Penguindrum because yeah I can't remember much from the first time. All that I remember is about the huge train accident that happened in Japan some time ago. So this gonna be me talking about the revelations that happens in the anime.
I can't say for sure if this is real-life tragedy, fiction or both and what's written here is based on my opinion (or maybe some internet finds and reads later after it ends).
Ringo, the one that loves fate. Tabuki that cannot hate and fight fate. The diary, the fate itself? idk from here it kinda seems complicated.
Natsume and Mario the same position as the 3 siblings. That other person that took the second half of the diary. Sanetoshi and the Black Bunnies. Is that Momoka inside the nowhere library? welp. Mary, possibly the siblings' parents which I really wonder what is their reason to make such a crime.
Also yes! The penguins! I think they are some kind of extra-terrestrial thing? Gosh it's hard to explain.
Currently on episode 14 which is half the anime. Will come back later to update.
Jyunna