Could you pretend it did not happen?

Feels like a useful phrase, but I probably don’t know how to make this sentence from scratch, so I might as well write it down 😅

なかったことにしてくれない？

• なかった – did not exist, did not happen
• こと – thing
• にする/にして – A を B にする means to treat A as B, to make A into B
• くれない – くれる means to do for me, くれない is would you not do it for me? which is more like “could you please do it for me”

In this sentence, there is a hidden item, like spilling the juice or an “oopsie” is the thing that we want to treat as なかったこと (the thing that didn’t happen).

The literal translation would be:
Treat it (the oopsie) as something that didn’t happen, could you please do it for me?

The context I heard this in was A and B almost had a one-night stand.

A: 昨日の夜のこと…
B: なかったことにしてくれない？