Metal

Huo Ling saw Fu Mingyan's expression and guessed what he is thinking. "Yes. These pests really came from our world." he told him, confirming Fu Mingyan's thought. 

"… pests as monsters?" Fu Mingyan asked with a hard to describe expression on his face. Talking to Huo Ling, he has already guessed the other's temper – as well as attitude. And he confirmed this when Huo Ling spoke again.

"No. The villainous kin of us." Huo Ling answered. 

Fu Mingyan. "…" I knew it. The 'pests' that he is referring to are not space monsters, but referring to 'people'! 

Meanwhile, the other grim reapers almost clapped due to Huo Ling's words spoken. They know that Huo Ling is eloquent, but not this good! 

Fu Mingyan's brow twitched. So these 'pests' really came from their world! He thought and sighed, deciding to change the topic. "Then, let us now talk about the first two favors." He told them.