Could you explain what it mean kill joy in this sentence
Oh, come on. Why do you have to be such a kill joy
A killjoy is a negative person who ruins all your fun.
Example: I was ecstatic Friday at 5:00 when I left work, since the weekend was finally here! "Yeah," grumbled Matt, "But Monday morning we'll all be back here at work...." My happy mood evaporated. "Why do you have to be such a killjoy?" I asked him.