Shall We Date?: War of Prayers - Inori no Otome

A crystal has chosen you to be its prayer maiden—the human vessel through which it maintains its protective power. The role comes with one absolute restriction: you must not fall in love with anyone. The knight assigned to guard you is honourable, attentive, and present every day. What grows between the two of you was not supposed to happen. Whether you keep your promise is the question the story poses and the player answers.