That Aqua can't register him as a bigger and badder predator than the average human is probably to Su-jin's benefit. He does so enjoy making friends with other creatures. There are some things he just can't even begin to bring up in conversations with even the most open-minded human. But he also can't reveal that he knows (strongly suspects) Aqua isn't human. Putting another creature in an awkward position like that isn't something he enjoys.

"Noon is a time," he explains as if it's not a strange thing to have to explain. "Mid-day. When the sun is directly overhead." He even uses his free hand to point straight up above them. "It's around the time a lot of people have their lunch meal."