This one is a little shorter, but then again, The Joy interested me far less than The Sorrow did.
The Joy was known for the emotion she carried into battle. She enjoyed the power she and her Cobra's held over the lives of their enemies. The Joy in battle was strong for her, that she carried her unborn child into battle. It was there, in the midst of blood and death that she was shot and forced into labor, giving birth to her son while the Cobra's protected her while she and the Sorrow got a look at their child. A long snake-shaped scar across her torso would always remind her of her child, the one that was taken from her shortly after.
When the Cobra's were disbanded at the end of World War II, she became known as The Boss. In 1964 she was forced to kill her lover, the father of her child, the Sorrow. What joy could she find now without the Sorrow and their child? With the memory that battle was in part responsible for the death of her lover. However, joy soon found her again in the form of a young man named Jack and she trained him, teaching him CQC and watching him grow until he took the name Naked Snake. She would take joy in helping him against Colonel Volgin, even though he didn't realize it, take joy in the fact that he created the Patriots for her after she died, leaving him to take up the title of Big Boss.
Even in death, she'd never stop feeling joy. Her teachings of CQC would be carried on, into Jack's children. The Les Enfants Terribles project, and they'd bring just as much joy to her in death as Jack, the Sorrow, and battle brought to her in life. And the joy still went, the Sorrow was with her in death and in time, her son joined them as well, despite his lack of knowledge regarding the Joy and the Sorrow.