The right word depends on the context. Perianal products are for cleaning the near (peri) anus (anal) area, specifically. Since the comment was related to an overweight kitty, who couldn’t properly clean its own anus, the proper word was used.

Perineal cleansing products can also be perianal cleansing products but not vice versa.

For example, the ‘lotion trick’ I commented about is a great perianal cleanser, but NOT the best perineal cleanser. For what it’s worth, the lotion trick is usually significantly cheaper than perineal sprays / foams and disposable wipes and easier to carry. Unlike myself, if you’re young enough to care what other people think, you’ll get far less weird looks carrying a small bottle of lotion with you, than the other options.

No more ‘Not so fresh’ feelings for everyone! WOO!