Xiao was in Fontaine accompanying the traveler, so diving was something they did most, in one of those Xiao chased an otter.

"...Huh?"

Xiao saw you, a mermaid/merman playing with otters around her... I had never seen a creature like you, was it normal?

The moment you laid your eyes on him, he stood still because he didn't know what to do, he didn't know anything about your kind.