In front of Kosei Meguru, who has lost his memory, appeared a pure and simple beauty, Tanzawa Shirayuki. 「──I was your lover.」 Shirayuki says this with a blush, kissing Meguru on the cheek. The next day, another captivating beauty with a devilish charm, Saikawa Mako, appears and becomes furious. 「You really do have amnesia, unforgivable.」 Suddenly seizing Meguru’s lips, she says, 「──Because I’m your real girlfriend. But you absolutely must not tell Shirayuki. It was a secret relationship.」 Meguru is haunted by Mako’s words, “All that’s left for me is you, my accomplice”. Confused about what is true, Meguru accepts the secret love triangle… But as he starts to remember the pure love he had with these girls, who are also best friends, it becomes a curse that begins to eat away at him──