Slay Demons and Gain Immortality

"You kidnapped us and fed us to monsters, why did you save us again?" "Because I'm not afraid of death." "You are now chasing monsters to heaven and earth because you are not afraid of death?" "No, now it's because I'm afraid of death!" A shabby second-hand mobile phone took me to a world where monsters were rampant, but it only gave me one hour to live. I had to constantly kill monsters and eliminate harm for the people in order to extend my survival time.