Because Zetta kept meeting new people and Ed hadn't done anything terrifically impressive in Zetta's eyes.

The book made a weird motion, frowned with irritation, muttered something about missing shoulders, then said, "Like I said, she reminds me of Pram. She doesn't seem any more evil than me... which isn't saying much, mind," he added with a glare to remind Katara that Zetta himself is EVIL EVIL EVIL. Right? EVIL.