What does one consider to be a beast? An unpleasant bloodsucking vampire? Frankenstein's creation? Shuichi Kagaya has a mystery. Other than having incredible evaluations and being gifted at sports, he isn't what one would call typical. Truth be told, Shuichi can't be viewed as human. One game changing morning, he woke up as a beast. With beast quality, an anomalous solid feeling of smell, enormous cushioned paws, and the downturn and self-loathing that comes subsequent to losing one's humankind, his life was out of nowhere turned over. Claire Aoki, the young lady he had chosen to spare, presently holds his mystery over his head. Claire is a cruel and totally contorted young lady, with no feeling of compassion toward the lives of others. Before meeting Shuichi, she was in the inquiry of beasts, planning to discover her beast sister. In spite of turning into a beast, Shuichi innocently keeps on clutching his human ethics, yet to what extent would one be able to toward the end in this excruciating method for living?