Luo hadn't fled, he was quite seriously injured. If he didn't address his wounds urgently, there was a high probability that his overall strength would slide further. Luo had already lost an arm, and if the situation continued to deteriorate, it was possible that he would keep falling through the ranks of fighters. He couldn't give up his future in martial arts.
Furthermore, the outcome of the battle outside was still uncertain. The combination of Casio and the Evil Mother was indeed filled with demonic Qi, overwhelming and oppressive. However, one of the Door Organization's Seven Kings, North King, was no pushover, not to mention the addition of two powerful allies to the battlefield. Luo was certain that the two auras he had sensed before entering the cave were heading towards Casio and the others!
Each aura seemed to be on the same level as North King.
