Tenseisha no Watashi wa Oshikatsu suru Tame Seijo ni Narimashita!

Iristella is reincarnated into the world of a game she played obsessively in her past life. To save her favorite character — Adolf, the knight commander doomed by an unavoidable death flag — she rises to become a saintess and even enters a contract marriage with him!! Now living under the same roof, will she be able to save Adolf from his tragic fate—!?