Start with a harmless truth
A friend who always arrives early, orders the same meal or guards the playlist gives you a small detail everyone can recognize. That detail is a better seed than a generic insult.
Try framing the prompt as a scene: “two friends compete over who makes the better late-night noodles.” The model can build a playful exchange around it.
Give each person a role
A duo gets more interesting when each performer has a perspective. One can brag; the other can gently dispute the claim. You only need a sentence describing the relationship.
Keep private information out of the prompt. An inside joke can stay funny without exposing something the person would not want shared.
Aim for a smile on replay
Before sending the clip, imagine both performers watching it with you. If the joke works only because one person is uncomfortable, rewrite the prompt. The best humorous video is one everybody wants to forward.