Willful, synonymous with Lily. She is an impulsive person who does whatever she wants, a representative of willfulness, but she is an absolute leader that no one can blame.
Maturity is synonymous with Cheng Qing. She is her absolute supporter, one of her willful capitals, but the most important partner in controlling her willfulness.
Free and easy is synonymous with Li Ke. He is a laissez-faire person who accompanies her to fool around, another person who will never grow up, but an infatuated man who will always be affected by everything about her.