HP: When Harry Returned to the Marauder Era

(Harry is gender-swapped to Harriet; includes a little GGAD.) After the Battle of Hogwarts ended, Harriet gazed at the ruins and at the friends and family who had died for victory, her heart heavy with sorrow. Then, without warning, the world spun around her. When she opened her eyes again, she was astonished to find herself back in the body of a little girl, standing in the familiar King's Cross Station. But why was it 1971? Could it be... she had returned to the year her parents began their studies? The gloomy Snape, the sunny and cheerful Lily, the kind and modest Lupin, the carefree James and Sirius, and Regulus, who first struggled in darkness before finally turning toward the light... Looking at these all-too-familiar faces, Harriet made up her mind. This time, she would save everyone.