The lifeforce of the big fish was extremely powerful, unlike anything Han Sen had ever seen before. He had seen much during his time in the Third God's Sanctuary, but nothing was comparable to that river fiend.
Han Sen grabbed Queen and did not move a muscle. The fish in front of them might have opened ten of its gene locks, so the last thing Han Sen wanted to risk was a provocation of its ire.
Furthermore, the school of fish following it were all sacred-blood at the very least. Their numbers alone would be overwhelming.
Queen did not know how powerful the fish were, but she knew Han Sen well-enough to know he wouldn't be so alert if they were not in peril. She complied with his obvious wish and stayed absolutely still.
The fish king must not have noticed the pair, so they merrily continued upstream.