What is the dirty meaning of playing chess?

There is also a dirty joke about playing chess: I played F with a netizen last night, and my sister's chess skill was too good and she lost. I became more and more depressed, and all the moves I didn't know before were integrated through her instructions. We fought all night until she finally surrendered and begged for mercy. Wake up in the morning and watch her sleep. I walked out of the door gently, held the chess in my arms and thought, I'll play chess with her next time. The significance of playing chess is also known by more and more people with the popularity of these jokes. There are also interpretations that chess has the meaning of love, and another reason is that there is a "cannon" in chess, so it generally implies the meaning of love.