Real name Hiroko Kageyama, she had been employed at Heaven's Gate, working closely with Madoka.
She became the countess after marrying a wealthy scientist/Count she worked with, because the man she loved, Terumichi Madoka, was already married and had a daughter.
When the Count died in Twin X, she inherited his immense fortune. She appeared to be the only survivor of the attack and lay in a coma for a few years, before deciding to find the children who could use the Dynamis. she searched for and found three children rumored to have magical powers, pulled them from some pretty bad situations, and raised them as her own.
She taught them to use their powers, and used them to fight the Gilgamesh, although they don't know her reasoning for asking them to do such.
She despises Kiyoko, most likely for being the daughter of the man she loved by another woman, and is much warmer towards Tatsuya because he looks exactly like Terumichi.
She has a mansion, but she lives in a huge, fancy hotel. She has a formal dinner with her makeshift family every night, and has the children driven everywhere in the hotel's car which eventually became hers.