Harem, shoujo, shounen, Slice-of-life.
Long ago (about 50 years), Japanese culture lived in relative obscurity. Then everything changed when Westernization attacked. In the 1970s and 80s, the United States began to import Japanese goods like crazy and with Japan came anime. Only the Weeaboo, master of all four genres could stop the west, and uphold the purity of the anime that they’d come to treasure.
Or that’s what they thought.
When I was growing up, I was really embarrassed to talk about things that I liked because I was afraid that everyone else hated those things and would, by my eleven year old logic, hate me. But the thing I was most embarrassed about was being a nerd. I watched a good amount of Dragonball Z growing up. And I hated it. They were always yelling and I never understood why, their fights took forever to end and there were no girls in it. But I still watched it, because it meant that I could stay up past my bedtime. (Two episodes of suffering for one less hour of sleep, that was just good math.)
Everyone else in my school didn’t have bedtimes. And they watched Jersey Shore. The most they knew about anime was Pokemon and I didn’t see an episode of that until I was almost in high school.
My anime education, animeducation, began in 10th grade. My friends at the time were anime junkies and I had to race to catch up. In my brief history of anime watching I’ve learned a few things.
*Note: Some of these things apply strictly to the harem genre (which I say is a guilty pleasure but is basically the only thing I watch)*
1. All girls in a 50 mile radius can only like one boy at a time.
And that one boy is the same boy that everyone likes. Even if there are nicer, more handsome, more interesting men in this area, all the girls like only this one. For some inexplicable reason, this boy is the only male creature that’s ever shown any of these girls even a modicum of kindness and for this reason and this reason alone he is the only man they’ll ever love.
Rosario and the Vampire
2. Girls can fight, but that makes them crazy and unlikely to have a love interest.
A girl that’ll slit your throat and watch your blood soak into her boots isn’t an ideal match, unless she’s built like an over inflated blow-up doll. Any woman that has skill in combat must immediately be objectified or nerfed by her emotions so that she’s less terrifying. 
Akame Ga Kill
3. Girls are constantly plagued with the thoughts of their beloved.
Whether they’re getting ready for bed or studying for a test that should be consuming all of their attention (but somehow doesn’t because studying in anime is irrelevant*) they’re thinking about that special guy. And even though they barely speak to him, their friends are definitely hearing all about him.
Kimi ni Todoke
4. Girls cannot talk.
Talkative girls are exposition fairies from the land of bad writing, annoying non-protagonists who are going to end up a forgotten plot device, or sassy main characters that border on infuriating.
Shows aimed towards younger girls, and featuring younger characters, often feature more outspoken female characters. Shows aimed at preteens and teenagers often feature shy girls or vocal and physically aggressive ladies.
Quiet, protagonist-like girls spend 75% of their time thinking about feelings that could easily be said out loud with little to no repercussions. Any time a confession of love needs to be made, all 14 years of schooling suddenly fly out the window and your brain loses the ability of cognitive thought.
5. Girls are both magical and useless.
I’ve seen six episodes of Sailor Moon. In all of them, Sailor Moon has to be encouraged by the dude in the tux to use her powers. Yes, she’s starting out and is bad at her job but you’re a whole magical girl. Why do you need some random kid to tell you to do the job that you were supposed to do already?
6. Females are strong as hell!
No matter how useless they’ve been through the entirety of the series each female character always comes through by doing something to recklessly endanger her life and help her comrades. Girls will take beatings left and right to stand up for what they believe in, defend their friends and help their loved ones. The levels of badassery that comes from a simple act by a character that knows she can’t fight throwing herself into the line of fire is over 9000. 
Seven Deadly Sins
*We all know anime characters only live until high school graduation, then they’re reincarnated into the next genre in the cycle.
