The abode of parasites

Back at his abode, Yang Qing found Ma Yuan absent Ma Ling, whose absence was because she had reached a critical stage in her treatment. The memory gu's effect not only on her memory but also on her soul had been completely removed and healed, especially its contamination on her soul.

Memory gu like most gus was highly toxic, and while the Ice emerald sect had contained the venom, Ma Ling's soul still had traces of contamination because of how long she had the gu in her and also how low her cultivation base had been when she had it placed in her. In the short term, it wouldn't have had that much of a detrimental effect, especially when one considered the cultivation art she practiced was of a cold-yin nature that was effective when handling toxic substances.