This is a story born in another timeline. Human beings are on the verge of extinction under the invasion of unknown life forms called angels; half-angels, that is what humans call girls who have been injected with angel blood and turned half of themselves into monsters, They tune with the holy relics left by the angels and guard the last fire of mankind. However, emotional memories will slowly disappear with the battle. In order to delay this process, a profession called instructors came into being. They were half-angels They are affectionately called Father, Oni-chan, and Darling. Their job is to help girls maintain their human hearts. This is Hongye's