This is Usage Tsukino, or rather Sailor Moon, though she is truly Princess Serenity. Later on she becomes Neo Queen Serenity.
The Moon Kingdom was destroyed and Queen Serenity sent Princess Serenity, the other sailor guardians, and two cats, Luna and Artemis, to Earth to be reborn. This is with the exception of Sailor Neptune, Uranus, Pluto, and of course Saturn. Saturn is part of the reason that the kingdom was destroyed.
Upon being reborn on Earth, Princess Serenity became Usagi Tsukino, born to Ikuko and Kenji Tsukino. She would later have a brother by the name of Shingo.
She would start off hating Mamoru, who was really the prince she was in love with. Eventually, she would warm up to him again to eventually marry him and have a child with him. Her child would become Chibi Usa.
She would go on to meet each of the guardians, all of them joining her to fight off many villains, some of which return from the destruction of the Moon Kingdom.
