The 'Knows What Sex Is' Grid is a popular alignment chart that categorizes characters based on their perceived sexual knowledge and activity. Usually presented as a four-quadrant table, it pits 'Knows what sex is' against 'Does not know what sex is' on the vertical axis, and 'Sexes' versus 'Does not sex' on the horizontal axis. This meme format gained significant traction on platforms like Tumblr and Twitter, where fans use it to sort characters from various fandoms, ranging from anime to video games. The humor stems from the often-absurd characterizations required to fit someone into categories like 'Doesn't know what sex is, sexes,' highlighting the pure or chaotic nature of fictional personas.