Despite all that Mo Jing knew about Li Meirong's suffering due to her accursed nature as a furnace, he did not know that his knowledge barely scratched the surface regarding her exposure to danger. For all he knew, she had simply lived her life in unfavorable circumstances as an outer sect disciple until a fortuitous encounter had elevated her to the rank of direct disciple to a Grandmaster. That, too, was also not achieved without the prodigal son of said grandmaster.
As a result, Mo Jing could not fully understand the reason for her peculiar response to his warning. He worried she was not taking the matter seriously enough, or would disregard his warning entirely.
"You may consider everything else I have said to be rubbish if you must," he exclaimed hastily, "but on this matter I must insist that you listen!" He regained his composure to explain a little more thoroughly, in the hopes that his somber attitude would emphasize the reality of the approaching danger.