For drawing a picture showing only a cat's rear end, it's easier if you first decide on the round shape. For the cat's body, you can omit the part that goes into the hole, and if you draw the visible rear end in a semicircle or teardrop shape, it will come together nicely. It is introduced that the line of the cat's body and how to draw the rear end look natural if you pay attention to roundness, which is also fundamental in drawing cats. (palmie.jp) 1. Draw the hole and the rear end First, draw the hole of the cat tower in a round shape. Draw the rear end in a larger circle, slightly protruding from that hole. Adding small bulges on the left and right makes it look more like a real rear end. 2. Draw the tail Make the tail thick at the base and thin at the tip. It looks cute whether you hold it straight up or bend it a little. Since a cat's tail strongly influences the impression of its shape, it is treated as an important point of interest even in pose references. (amazon.co.jp) 3. Show a little of the hind legs Showing just a little of the hind legs from below or the sides of the hole enhances the cat-like feel. Small circles are enough for the toes. For a calico cat, it will look right if you place black and brown irregularly on a white base. Don't make it too symmetrical; a rough approach like placing black on one side of the rear end and brown on the other is fine. As you can see in the reference images, calico cats look neat and easy to view when their color patches are placed somewhat large.