"Those at Rank 0 have a potential lifespan of 100 years." As Valyr began to read through the various values the book had given him on the maximum lifespans one could hope to achieve per rank, his eyes glistened with interest, committing every bit of information he got from the book to memory. "Ascending to Rank 1 increases this by 50%, giving those at Rank 1 a potential lifespan of 150 years."
"On the other hand, ascending to Rank 2 increases one's potential lifespan by another 50 years, which allows a Rank 2 class holder to live twice the maximum natural lifespan a Rank 0 class holder could achieve as long as they have a high VIT stat."