I mean, TBF, being bathed and having your butt glands squeezed isn't everyone's cup of tea (and no kink shaming from me for anyone who does dig it). He does look like a splendid little cowboy though. :)
Sometimes dogs’ anal glands don’t express naturally, and they can get impacted. That’s bad news and also gross. Groomers typically express them in a normal groom. You can also learn to do it yourself, or have the vet (tech) do it for a fee.