Welcome back, anime fans and stans. There is a lot of anime out there - probably way, way more than you think. The anime industry is massive, and there are some real niche subjects being touched upon. For example, there is an anime, Cells at Work!, that features anthropomorphic human blood cells going about their business in the body. It's a but like that weird early 2000s movie, Osmosis Jones, but with more Japanese antics and humor. The show Bungo Stray Dogs features characters based off of famous literary authors; their powers are even based on books, poems, and short stories by those authors.
Needless to say, there are an infinite amount of subjects that anime can touch upon. It is no surprise then, that in the sea of all anime, every date in the Roman calendar has been mentioned in some way - sometimes in the dialogue, sometimes on a literal calendar, and sometimes hinted at in the background. Enjoy this collection of screenshots from a wide variety of anime that mention every date in the month of September.