Tell them an elaborate list of fake plans you've made to the point where they don't see the need to stay over anymore?

They probably knew exactly what they were doing, damn cockblockers

Moan really loud with your bf in your room, either they'll leave awkwardly or they will just do it in the living room

Sometimes grandparents are cooler than parents, if this is the case, maybe you can still invite your boyfriend.

Maybe your parents asked them to come over? ;P

Just say you have stuff to do and could use some 'you' time. That basically gives them no choice but to leave

how about just fk your bf at his house and stop going behind your parents backs?

Judging solely by your tone (as you sound like a teenager hoping for the opportunity to do something your parents wouldn't allow), I feel as though maybe they were asked by your parents to stay with you, rather than deciding on their own accord. Which sucks either way, but you may as well try to have fun with them. They're likely not gonna be around for much longer.

I pretty sure your parents call them.

Or, you could make the best of the situation and hang out with your grandparents? I can sincerely say I regret not spending more time with the elders in my family while I had the chance- your boyfriend will be there at the end of the week, I'm pretty sure.