@MCX01 I don’t think it’s that simple. Based on the first generation story it looks like the succeeding mc (reincarnation) is the hero that similarly to the 1st gen transferred her power into her lover either unintentionally or through the church manipulating her unnoticed. As the moment she is required to deal the final blow she has a breakdown, runs away afraid of the memories, kills herself, it loops as you said or something else. Maybe she simply never could kill the demon king knowing it was someone important to her. If she was repeatedly killed perhaps her lover of each life similarly become demon king’s or in this case are the body double/shadow that the next hero defeats.