Why? Hmm...
Because I couldn't sleep, tossing and turning in a panic in the middle of the night before a blood test the next day, and the idea of starting a vampire story suddenly popped into my head with a "bang"...
What would happen if a discarded, defective "first human" were found in a garbage dump by a vampire who had long since reformed, grown old in spirit, and settled into a quiet life...
Hmm, since modern people wear too much foundation and are too much trouble to seduce, the vampire has lost all ambition and now just wants to earn money to buy blood packs. And now that there's a blood bank, the obvious goal is to earn enough to support the family!