ka-bunk-a-bunk
A butt that’s not good, not bad, but it’s there and it’s just being a butt.
That ka-bunk-a-bunk is just being a butt, like it's got nothing better to do.
My dog's ka-bunk-a-bunk is just there, like it’s confused.
I saw this guy’s ka-bunk-a-bunk and it was just there, like it didn't even know it was a ka-bunk-a-bunk.