My Secret Boyfriend Has a Public Girlfriend

Elena has dated Lucien in secret for three years. At their graduation banquet, the magic resonance crystal pairs Lucien with his academic rival Seraphina as two-month contract lovers. The whole academy ships this enemies-to-lovers couple, and Lucien asks Elena to wait. But Elena holds an offer from a prestigious overseas academy. She leaves for good, leaving Lucien to regret his choice too late.