There is one feature of the system that Qin Yi hasn't tried until now; maybe it can solve his current problem.
Maybe he could try experimenting with this feature later with bad guys. After all, extracting a real thing from bad guys won't cause him guilt.
Although what Qin Yi had been doing all along was no different from stealing, it didn't harm the targets at all. In the end, all he did just copied their possessions.
However, Extreme Extraction was an entirely different matter. When using this feature, everything belonging to the target can be stolen except for anything that can kill them directly or indirectly.
Martial aptitude is no exception. Therefore, if Qin Yi wanted his family to be able to cultivate, the only option he had was to steal someone else's martial aptitude.
Moreover, to avoid guilt, the people who deserve to be targeted are the bad guys, people who had a grudge against him, for instance.