"She's mostly friendly but may run if you try to catch her - she's kind of a jerk too. She has opinions about things," Irwin wrote on the poster.
Irwin initially suspected a neighbor had found Babou and taken her in, but warned she "is not the kind of cat people would keep."
"She likes to sit on you, but doesn't want you to touch her," Irwin said. "She likes to sleep on your head and she's a talker. She has opinions about things and is very verbal. She will sit next to you, stare you in the face, and start a conversation that is a bit uppity."
Irwin and her husband found Babou in a parking lot in Miami in 2011 when they were actually charmed by her sweet personality.
"I had hurt my neck and my husband went into Target to get some medication for me and I said, 'Oh, God, we can't leave her here or she'll get run over,'" Irwin told ABC News. "She ran across the parking lot and jumped into my arms. She was the coolest cat for six months and then she got spayed and that changed everything."
Despite lamenting Babou's jerk attitude, Irwin fantasized about a West Side Story-style reunion with her missing pet.
"It's going to be like the Sharks and the Jets and she's going to be leading this team of wild cats," she said. "She'll show up in two weeks missing an ear and patches of hair and smoking a cigarette all like, 'You should see the other guy. I'd tell you where he is but then I'd have to kill you."
Their actual reunion came on June 13 after she unsuccessfully searched near "two places people had seen similar cats" in rain.
"Babou walked up to our front door in the pouring rain and meowed LOUDLY until we let her inside," Irwin said. "She's a little thinner and totally soaked but home safe and sound."