爸爸说外裤内穿是超人
[bà bà shuō wài kù nèi chuān shì chāo rén]
A playful nickname derived from childhood imagination, suggesting a funny or adorable aspect of growing up. It humorously translates to something like: 'dad said if you wear outside trousers inside your pajamas then you are Superman,' evoking nostalgic amusement.