What Should I Do If All My Female Disciples Are Yanderes?

The seven great witches wreak havoc on the world, destroying all life in their path and not even a blade of grass can grow. The Heavenly Dao System came across the long river of time and landed on their common master, Xue Wuchen. System: "As long as you, host, can teach these female devils to be useless! Prevent them from harming the mainland in the future and save the way of heaven, I will return you ten thousand times the resources! Help you ascend to the level of Immortal Emperor!" Xue Wuchen: "Are you sure? Any method will do?" System: "Of course! But you have to be careful, these female villains are all paranoid. If you are not careful, they will take advantage of you!" Xue Wuchen: "Don't worry, I know what's going on." Many years later—— System: "I asked you to teach them to be useless, how can you teach them to be yanderes who can't live without you?!" Xue Wuchen: "Just tell me whether the mainland has been saved!" System: "Although the mainland was indeed rescued... But they... Forget it, they are here, just wish yourself well!" Xue Wuchen: "You can save the world by sacrificing me. Why not?" After some time... "The system save me!!"