Immortality CTOA

As you wake up one morning, you see a shadowy figure looming above you. They are wearing a black cloak that conceals their face but you make out a pair of glowing red eyes. Immediately avoiding any eye contact, you easily go to the figure's skeletal hand which is holding a scythe. will isn't that just great! You wake up to see the Grim Reaper. Just as you start pleading for your life. the dark entity specks in a raspy voice "I am not here to reclaim you. the universe does not have enough static souls Some creatures are given eternal life to combat the transient nature of reality." Your deathly visitor pulls a large and dusty old tome out of his cloak and drops it on your chest.