How do you remove cat poop stain from a leather couch?

Go to a pet supply store (the large chain stores usually have these products and better prices) and buy a product made with enzymes to remove pet stains. Read the label and the right ones will tell you that the product is effective for urine, feces, vomit, blood and other stains caused by pets. These work just as well on human stains if the feces is not from a pet, and they work better than the products sold for carpet and furniture cleaning. Follow the instructions on the label which will include first removing any large pieces and follow with the use of the product. One that is very good is called "Nature's Miracle", but there are other brands that you will find in the pet supply store that have the same enzymatic action. Another brand of similar cleaner you can find in some grocery stores is called "Incredible!". It is very good on smaller stains, but for the larger stains, you can get Nature's Miracle by the gallon.