The Strongest Subordinate System

After traveling through time and being reborn, he just became a refugee. In order to survive, Chen Li became a guard for a noble family. Then the strongest subordinate's system awakens and suddenly becomes ten times stronger than the strongest person in this family... What should I do? Why! Being invincible is really lonely. This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.