The talking duck was actually NOT the weirdest thing that Mirio had seen. After all, have you seen Principal Nehzu?

"Ah, sorry ma'am, you might be confusing me with someone else!" Exclaimed Mirio with a laugh, rubbing his head embarrassed. "Storkules huh? Sounds like a fine hero though! I'm Mirio Togata. I must say ma'am, your feathers are very glossy, do you use Brilliance Shampoo from back home?"

He's assuming of course, she's a duck who has a Quirk but looks can be deceiving.