Yuki Amano's life runs on clean code and predictable logic. His greatest ambition is building the perfect system, a quiet world where every problem has a solution. But when a chance encounter in a dark alley plunges him into a hidden war of magic, his carefully structured reality collapses. He's cornered not by a bug in his code, but by Aya Lefebvre, the beautiful, enigmatic foreign transfer student who is infinitely more than she appears. Forced into a dangerous contract that binds him to her as her "boyfriend," Yuki must now use his digital genius to navigate a world of ancient spells, shadowy organizations, and supernatural threats.