Hokay, so I just started watchin penguin drum and I have to say it is AWESOME. One thing that keeps bugging me however are the references that show up EVERY episode especially the ones related to Revolutionary girl utena a magical girl show that feels eerily similar to penguin drum. Here are some similarities bettween penguin drum and other animes that i have found.
every episode himari transforms into the mysterious penguin lady, and they sing a song and have a whole video dedicated to her scene, much like the pre-fight cutscenes in Utena
not only that but the student concil scenes in utena always had a elevator backdrop type-thing behind the student council members
same thing happens in penguin drumalot of the characters in Penguin drum have a uncanny likeness to Utena characters:such as a version of jouji:they even have the same cutthroat personality.there is also an odd touga and utena combination for that pink haired woman
also similar personalities.notice the penguin above.theres also alot of moments where lady oscar or marie antoinette appear from the series "rose of versailles" which utena is loosely based onthat woman is lady oscar loland yurie makes a good marie antoinettealot of the faces come from older animeand a few modern references like excel sagaand even casablancaand the one everyone saw: