The simple way to get any information without getting your hands was... Hypnosis! Instead of physical torture, it was better to torture someone mentally until they lose their own mind.
Ru's personal knowledge of hypnosis was limited. It was enough to shock the normal people but before the grandmaster level hypnosis of Rong, her skills were not even worth mentioning. Her skills were limited in this field which she just picked up because she was bored. Besides, if she had learned it from her master back at home, her skills might not be inferior to Rong's but Ru never had any interest back then.
