Transcript:
Goat: Hey, Pig. Do you have a game tonight? Pig: Yeah, but I don't like the other team. They're ruthless. Goat: And your team's not? Pig: No, we're pretty ruth. Goat: Not sure that's a word. Pig: In fact, our center's a gruntled postal worker.
Yes, ruth IS a noun – now out of use, meaning pity. So, ruthless = pitiless.