If I Travel Through Time, I Will Be Invincible

System: Host, do you want to make a counterattack? Do you want to be invincible in the world? Aoki: I don't need it! System: Why? Aoki: Because I am invincible! System: It's okay, I've helped you upgrade the world! If you don't get stronger, you will die in a short time. Complete the task obediently (>^ω^<) Aoki: You are so damn cruel! System: Thank you for the compliment! Aoki: How do I have such a system (っ╥╯╰╥c)