Tan Helin was a clever girl who attracted much attention in her childhood. She liked to be different and liked to be noticed and praised. She was active, smart, and powerful, so she and the people around her thought she would become an Alpha. However, after the differentiation ended relatively early relative to her age, all her glory came to an abrupt end - she became a Beta.
Only after she lost all the powers that Alphas were more qualified to enjoy did she understand the injustice of the world.