Novel Transmigration : Extra's Life

Eighteen year old Alex transmigrated as a side character into one of his favorite novel. Dating the male leads sister was one thing, but can he survive in this harsh world to enjoy it? ----------------------- After dying in a bizarre phenomenon, his soul possessed the dead body of Alex. A twenty-eight-year-old side character in a novel called Outerworlds. A novel where people with superpowers fight to protect the planet and its inhabitants from the threat of the Outerworld. Can the lonely dead eighteen-year-old soul prevent himself from getting killed, again? Armed with the knowledge about the future. Should he become strong enough that nothing can kill him, again? Or should he just chill and enjoy his life? What made him transmigrate? How will he fare in a world full of superhumans? Let's read and find out.