What exactly does knowing the five accomplish? You've given nothing but vague answers to what amounts to nothing more than essentially "just because this will make me feel better" which is not a valid reason to intrude on his privacy.

This is not a humble brag, but I'm using my situation as a way to illustrate a point. Personally I've been with over 40 different women (don't know the exact number, I stopped counting years ago), some of which I've forgotten their names, some of which I've forgotten all together. When I was in bed with a woman the other day I met from Reddit, she remarked something to the effect of "I don't know why you put up an ad on Reddit, you could be pulling some major tail!"

I didn't say anything other than smile and kiss her on the lips. Why? Because nothing good would come of me opening my mouth. I didn't want her to feel like a disposable woman and in the end she would just ask questions exactly like you're doing or possibly question her self worth. Or possibly have her question the kind of man I am because of the amount of partners I have had. If I did open my mouth then I just look like I'm bragging, The biggest personal reason I didn't open my mouth is because I'm still good friends with some of these women I've slept with in the past.

Your boyfriend may be in a similar situation and the only thing you knowing their names is going to generate is animosity or weirdness. You're going to imagine them naked if you see them or you're going to question why he did certain things with them and not with you. Or you'll question why one of them was super hot and what he sees in you. You see where this is headed.

He's already given you a segue into asking about the numbers. My advice to you is ignore the names and respect his privacy or this is going to blow up in your face. Focus on why he lied to you.