If you are male, your clothes will automatically regenerate after each battle. Because of this there is no need for you to own more than one outfit. You may continue to wear the same clothes over and over again.
If you are female, your clothes will always rip in a fanservice-like fashion. While your clothes will not regenerate immediately, they will have recovered by the next episode. You, too, can wear the same outfit over and over again.
To the Aragami, gravity is only 1/6 of what it is to human beings. This is the equivalent of walking on the moon, which is why Kusanagi can leap about with little effort.
Momiji is required to show her panties at least once an episode. Likewise, Sakura is required to expose her cleavage. Koume is not required to show anything except an unconditional zest for blowing things up.
If you don't know what it is, blow it up.
The aragami men must fight whenever they are within a 100 mile radius of each other and they are required, by the order of nature, to alternately call each other "imperfect" and "jerk" as much as possible.
If a character ever knew Kaede at any point in the past they are required to have a positive flashback of her where they can remember how fond they were of her, or how sorry they felt for her, or how kind she was, no matter how she is currently behaving.
If you do know what it is, you probably still want to blow it up.
If you are arrogant, annoying, or trying to blow up Japan with nuclear weapons, then you are probably an American.
It will not be considered perverted nor pedophilia if a person falls in love with someone half their age or twice their age. Equally, nobody will be looked down upon for hitting on a girl and/or asking her out/proposing marriage when said girl is in her early high school years and they're a fully functional adult. Such law applies directly to Sugishita, Kunikida, Takeuchi, and Yaegashi.
Opposites always attract. Always. This would be why Yaegashi and Koume are engaged to be married and Kusanagi and Momiji are dating.
The moon will always be full. It will never follow the natural lunar calendar.
If the moon is ever moved from its natural orbit, it will not have an effect whatsoever on the Earth's weather and tidal calendars.
Even when in extreme danger, the secret service will not be able to move the most powerful figure in the government, even if said person will most surely be killed if he doesn't go.
No matter who you are, if you are blown into something so hard that it forms a massive crater, you come out only slightly bruised. Mainly applies to Kusanagi and Murakumo.
Everyone will not have any fashion sense whatsoever, and never be criticized for their sad use of clothing. Such case mainly applies to Yaegashi, who can't seem to realize that light blue suit coat with a baby pink shirt with yellow pants is about as clashy is one can get.
Every single person is obsessed over something. Momiji is obsessed over Kusanagi, Kusanagi is obsessed with Aragami, Matsudaira is obsessed with work, Yaegashi is obsessed with data, Koume is obsessed with guns, Kunikida is obsessed with the government, Takeuchi is obsessed with Kunikida, Sugishita is obsessed over girls, and Sakura is obsessed with herself.
Hair any longer than a stubble will always billow gracefully around, even when there is no wind.
All characters must look either less their age or more their age. This is most true with Kunikida, for while he is 40, he looks 60. Momiji, while 16, looks 14, and Kusanagi, while 18, looks to be at least 22.
No matter how much blood you lose, it never really affects you in any way. Such is the case with Kusanagi, Yaegashi, and Koume, who have all lost at least a gallon of blood at some point, and yet never feel woozy nor faint from the loss.
No matter how long your hair is, it will never get caught on anything and it will never get in your way. This is mostly true with Koume and Ryoko, both of whom have hair either in their eyes or long enough to always get in their way, yet it never phases them.
Hair accessories and other items will never move. Ever. Such items include Momiji's bow.
No matter which way you're facing or how many times you turn around...you will always be walking into the wind.