Carassius auratus represents three generations of children of TF family in Zhang Zeyu, Zhang Jihe, because there is a cp named Yu Ji in Zhang Zeyu, Zhang Jihe, and then Carassius auratus and Yu Ji are homophonic.

Cp generally refers to pairing. Pairing (English name: Coupling, Japanese name: カップリング), referred to as cp, is an online buzzword, which comes from Japanese ACGN peer circle. The original meaning refers to the pairing of people and love, which is mainly used in the circle of people in the second dimension ACGN.