My Tilapia Reincarnated Into a Twelve-Year-Old Girl

The full title is "My Pet Tilapia Reincarnated into a 12-Year-Old Girl and Now She's Living Her Life as My Little Sister" A seventeen-year-old otaku named Betoy woke up one day and was notified that his pet tilapia (which he doesn't care much of) reincarnated into a 12-year-old girl! Or at least, that was his Father Kanor told him.