Quote from Marshall in The Mermaid Theory
Robin: And that's why we never hang out alone? Marshall: Yes. As Lily's best friend, you are the last person on the planet who's allowed to turn into a mermaid. Robin: Wait, does that mean that I'm a manatee right now? Marshall: Big-time manatee. Robin: Whoa. What were those sailors thinking? Marshall: Huh. I don't know. Being out at sea can do crazy things to a man.