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How about the digestive system?
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Nostrils and mouth are connected, topologically you could therefore have ass to left nostril with the mouth being an own opening!
That said I really really hope you forgot your uthera at least. Which is a curious question back to the subject: is it a topological hole if the opening is only to the insides of the corpus? (Thinking about the reproductive parts of either sex specifically).
I think topologically they don't count, that's why I didn't count the urether/urethra.