Time Keepers are selected for their fairness. They are tasked with keeping the timeline on course. Time Keepers are granted the rare gift of immortality in exchange for their service (they are not allowed any close attachments to anyone except other Time Keepers and only then is it allowed to be platonic in nature). Time keepers do not go back in time to prevent things from happening or go into the future for warnings but instead ensure that no one illegally alters time.

I will be playing the role of a time keeper and the idea I have is that MC didn't become a Time Keeper until after YC's death, they were romantically involved. Having finally passed the training and allowed to travel through time they are assigned the mission of undoing illegal time travel events and every time period they visit they find YC.

PM me if interested.