How do i reply rudely but nicely?

This is what you can say....." I appreciate your nice gesture on making an attempt to have a night of supposible fun, but I would like to p on that. The only thing I can picture you doing this weekend is having a few bottles of bubbly and having science define it from there......so I hope you don't disappoint yourself with well yourself....enjoy!" or either all you can do it just email back and say "hahahaa yeah right" something along that line I guess. Hope I kind of helped.