In the aftermath of the Tokyo Olympics' cancellation due to terrorist attacks, a unique international school now occupies the once vibrant site. Concealed within the student body are seven extraordinary teenagers dubbed 'Flowers,' serving as covert operatives for a UN intelligence agency. Tasked with eliminating peers possessing similar abilities, these youths operate under the threat of their families held captive by the organization. Failure is not an option, as it would spell doom for both the Flowers and their loved ones. Amidst this harrowing ordeal, the tale unfolds, exploring their relentless struggle against a merciless destiny and the enduring human spirit that seeks solace amidst the darkness.