Shu met Oma on top of a mountain that divided their two villages, but because they belonged to different tribes that were warring, they were forbidden to see each other. However, their love was strong and they managed to find a way to continue meeting. The two were able to learn earthbending from the badgermoles that dwelt within the mountain, and using their bending, were able to carve out elaborate tunnels where they continued to meet secretly.
The two lovers continued their meetings until one fateful day when Shu was killed in the war between their villages. Devastated by her loss, Oma unleashed a potent display of her earthbending prowess, but rather than destroying the two villages, she declared the war between them over. Together, both villages helped her build a new city where they would peacefully coexist. The great city came to be named Omashu as a monument to the two lovers.
Oma is phonetically similar to eomma (엄마), which means "mother" in Korean. This may refer to Oma being the mother of earthbending.
Oma bore a very close resemblance to Juliet from William Shakespeare's play Romeo and Juliet. Like Juliet, Oma belonged to a territory at war with that of a man she loved. Even though they were considered enemies, they fell in love with each other. However, unlike Juliet, she did not meet a tragic end. In this regard, her fate is more like that of Maria in West Side Story, a musical inspired by Romeo and Juliet, who manages to survive but loses her male lover.