Doronavirus-20 Apocalypse

A worldwide pandemic spread out. DOVID-20, or Dorona Virus Disease, was discovered in the year 2020. When a new found vaccine was made in attempt to cure the virus, it turned humans into bloodthirsty and mindless man-eating monsters instead. Fast forward 10 years into the future, a 42-year old man was killed by an insanely strong Infected, sacrificing himself to the save the hope of the human race. "Hmm? Why am I back in my room? Why is my arms free of scars?!" .That was when Erza realized, he went back in time before the apocalypse happened.