Seraphine: The Aspect of Joy

Seraphine was born in Piltover, on the edge of Zaun, with a rare sensitivity to magic. The magic Piltover surrounded her with created music and she composed songs to it. Her voice made everyone who heard it happy and quelled fights. Even those from Zaun loved to hear her sing. However, the magic of Piltover soon began to bore her and she sought different magic to create different music. In her research, she learned of ancient magic on Mount Targon and began to prep for her journey.

The mountain proved to be harsh terrain, and Seraphine made most of the journey bundled in a blanket, the snow making her red hair almost white. Yet, still, she journeyed on.
The nights were hard, and some days, she thought she wouldn't survive, but she didn't hear the magic she so craved.
When she finally reached the peak, she heard it. A quiet, but gentle song, unlike anything she had heard before. She sang out to it and heard it reply as she made her way towards it.
She found a small ball of magic and it danced in her palms. She sang to it once more before it slammed itself into her chest and became one with her.
At first, Seraphine felt a warm light fill her, moving within her as she was sure the magic was. Then, that light turned into searing pain and she fell to her knees, gripping the snow beneath her as a pillar of light formed around her.
When the pain and the light faded, Seraphine found herself clothed in a skirt and a short-sleeved top, yet she didn't feel the cold. Her hair had turned pink and something stuck out of the snow. When she uncovered it, she found a platform that reacted to her touch. It sang as the magic had before it and she sang back to it, placing her feet on it and getting used to its movements.
"You are the Aspect of Joy, Seraphine," a voice rang in her head. "Go spread love and happiness around Runeterra. That is your age-old mission, the one you have been destined to fulfil."

So that's what she did. Her loved ones faded with time, but their song remained in her heart for her to give to the people of Runeterra.