As for heart demons, Qin Fengming had seen some descriptions in various ancient texts. However, none of them explained the matter in much detail. They merely stated that an oath sworn to a heart demon was the most reliable contract of all.
As long as one swore an oath to a heart demon using a special talisman, no one would dare casually go back on it.
But Qin Fengming only had a vague understanding of the specifics. Now that he heard the purple Nascent Soul explain it, he was deeply alarmed. So the oath to a heart demon concealed such dangers.
Qin Fengming had originally thought that as long as he did not violate the oath made through the blood curse, nothing bad would happen.
But now, he had gained a new understanding. The purple Nascent Soul before him was saying that as long as one swore an oath to a heart demon, then when one later broke through to a higher realm, something bad would happen even without violating the oath. This realization imperceptibly stirred a trace of wariness in Qin Fengming.
Back when he had been at Manghuang Mountain, he had sworn a blood curse in front of five Great Cultivators at the late Nascent Soul stage. Although he had only stated that he would never do anything in this life that harmed Manghuang Mountain,
after learning of his five masters' plans, he had developed some contempt for Manghuang Mountain. Now that he had heard the purple Nascent Soul's words, this Qin's heart trembled violently once more.
With the abilities of his five masters, they naturally knew how frightening this blood curse was. Their insistence on it clearly meant that they wanted Qin Fengming to devote his entire life to Manghuang Mountain and never betray it. Even if