...
"You will only be a burden."
When Shin heard those words, he could not help but feel a little uncomfortable. But he knew that what David was saying was true. He and Leonard would only be a burden if they got involved in this battle.
He might be able to fight Shaun earlier despite him having a lower realm, but that was only because of the latter going easy on him during their battle. He took advantage of the carelessness of his opponent during the battle.
But this time, he knew that Shaun would no longer be foolish now that he had become a mutated monster.
A single look at these mutated humans was more than enough for Shin to tell that they had a certain degree of intelligence. But at the same time, he could also see that they were not conscious enough to be called alive.