她纯洁她无瑕我世故我复杂
[tā chún jié tā wú xiá wŏ shì gù wŏ fù zá]
This nickname contrasts the purity and innocence of 'her' against the worldliness and complexity of 'me'. It implies a disparity between two distinct personalities or attitudes: one is untouched by life's hardships, while the other has become hardened and complex from experience.