News of men's death and the fact that her house was haunted by screams spread all over the entire town, Liu Hui Ying knew that sooner or later she will be dragged into a heavy mess and coupled with the guilt she felt towards her sister, she was willing to tie her sister's soul with hers.
It was a foolish experiment but she somehow manage to succeed in it.
Now that her sister's soul was within her body, she was able to restrain things like death with the heavy yin and cadaveric Qi, as long as she wasn't willing a person wouldn't die easily.
The maid whose heart was wrapped up by the Yin energy of the dead wouldn't die unless Liu Hui Ying was willing to retract the Yin energy from her heart. She would feel the pain of her heart being torn and pierced but she will never die, not unless Liu Hui Ying agrees.