Marlene McKinnon was the most beautiful girl in all of Hogwarts. Her blonde hair always curled to just above her shoulders, and her eyes were akin to the lake's reflection of the sky. All the boys wanted her, and all the girls loved her; even the professors took pride in having her as a student. In short, she was everything Sirius Black wasn't, but he had a secret.
For you see, Marlene was from the prestigious McKinnon family, as Sirius was from the Black family. Both were Pureblood families with great reputations to upkeep, so what better for them to have done than to arrange for the marriage of their heirs?
Yes, Marlene, sweet and beautiful Marlene was his fiancée throughout his years at Hogwarts. And though many men vied for her affection, none would prevail, for Marlene was a girl of principle, and left her heart to Sirius. Even though he was disowned from his family, Marlene kept her word.
Shortly after they both left school, the two were married, albeit secretly. They met long after prying eyes had gone to bed. Only close friends, such as Lily and James Potter, knew of their tryst. It was dangerous in those times to make their relationship open, for his relatives were on the opposite side of the war.
Things were alright for a while. Marlene even became with child. But, if it not for the Dark Lord, then maybe they would have stayed like that.
An attack on their humble home caused great injuries to Marlene, who was the only one there at the time. Sirius returned and was not able to even recognise her; it was such a sight to behold.
Needless to say, Marlene lost the child, and the event began to tear them apart. Within months, they separated.
Marlene McKinnon died in 1981, only a year after she and her husband divorced. Sirius never forgave himself for letting her die, even years after the fact.
When in Azkaban, Bellatrix Lestrange would often complain about his moaning. Over and over again, Sirius could be heard howling the same thing:
"She turned and walked away without ever looking back."