Exchange of All Things: Kill the Enemy and Touch the Corpse at the Beginning

The protagonist redeemed the magic charm from the beginning but didn't use it. In order to advance the plot, he waited until his sister was about to die before using it.

At the beginning, he used the system to kill his entire family. If he had good things, he would not use them and had to wait until the last moment. The protagonist is the kind of person who explodes firecrackers on top of cow dung and refuses to leave until the last moment, only to end up with a nasty look on his face.