Ren's feed

so (american)mc got turned into a vampire in the 18-1900s then eaten when a bat, the creature who ate him got picked up by scientists or something and they froze them, years years later after being shipped to japan (?) he unfroze and turned into a human
he later on helps figuring out murders with his nose

i could go into more detail but i feel like the ones who know it will catch on by this description