I've reviewed your chapter and made some grammar and punctuation corrections while adjusting paragraph breaks for better readability. Here's the revised version:
"Are you okay? And what the hell was that?" Giuseppe asked, looking back at the middle of his shop that was now completely empty.
Luan grunted, supporting his head with his hand. "I don't know. But what I do know is that it's related to my sigil."
Giuseppe stared at Luan for a while, unsure what to do next. A sigil was a person's deepest secret except for the name; no one knew anything about another's sigil.
Asking the young master to share would be overstepping, but his curiosity was killing him. Scratching his head, he looked at Grant, who seemed to share the same thoughts.
