A “Knot” is kind of like a bulb type thing in the Seme’s penis that swells when they are aroused and keeps them locked inside their Uke during sex to increase chances of getting the Uke pregnant, this is called “Knotting”.
You may feel your favorite manga should be gathered together into distinct categories for your own reference and, now, you can do this with a LIST. After you've created your list or lists, you can proudly recommend them to other manga fans to showcase and share your taste in manga.
Height / Size Difference
Everyone of age (to the best of my knowledge)
Cover image is from “Perfect Body”