Energy Transference
Mira searched through Derek's spatial ring and found a jade slip titled "Yin-Yang Energy Transference Technique". With a quick scan, Mira understood the basic principles of the technique.
This technique was more of an Auxiliary Cultivation Technique because it mainly taught you how to absorb and refine your partner's fluids during sex. For women, these fluids were described as Yin energy, while for men, they were Yang energy.
What Mira found interesting was how men were able to take a woman's 'yin energy' and refine it into something they could use and vice versa. Unfortunately, it didn't go any further than that.
The technique didn't mention anything about boosting one's Dao Comprehension or improving one's affinity, but Mira wasn't expecting something like that in the first place. Perhaps not even the elders of the Main Yin-Yang Sect kept stuff like that on them, much less a kid at a branch Sect.