Predicament

So my boyfriend and I have been dating now for almost 7 months. He’s been wanting to try a threesome for the past a couple of weeks. The only way I’d be able to go through with it is if every individual is drunk. Plus this third person would be one of my closest friends (we agreed but idk still feels weird) Last night we all went out to a bar and he was quite persistent that that night should be the night. Am I doing something wrong in our relationship for him to want to do this so badly? Does he just want to try something new? Any thoughts would be greatly appreciated....