为什么拉完勾以后就要上吊

This username humorously refers to a traditional Chinese gesture where two people hold pinky fingers and make a promise, symbolizing 'pulling hooks.' The phrase then humorously exaggerates by suggesting one should hang themselves after making the promise, which is absurd and unlikely, adding a layer of sarcasm. This kind of playful language often signifies the lighthearted nature of making jokes about commitments.