You Haven't Even Gone to College Yet, and You're Already Invincible in the World?

In a world invaded by thousands of races, how dare a young man hold a long sword in his hand and resist bravely! Jiang Jie, accidentally obtained the killing system, dare to think, dare to do, and lead the human race to the highest level! "Even if thousands of people in this human world bully me, I, Jiang Jie, will cut them off with a single blow." This is Jiang Jie's declaration of struggle!