Who the heck knows what's "Normal" today, especially among charms, LOL. Since I've been married, I've been with six, I think. A few more from before I was married, so maybe a dozen total. Not too skanky
We're a lifestyle couple but I don't full swap often. We love to go to the parties and dance and cut up and we have a small circle of friends that we do a bit more with. Still, most of that is soft swap. Since we've started swinging, always safe sex except for oral. And on that note, I really haven't had too many more partners when you factor in oral. You can catch a few of the nastier STDs that way too.
Lately I've been posing quite a bit with my best friend's husband which is a weird and fun dynamic. We've had sex but not on my site. He has a terrible time with safe sex, he just can't seem to stay hard with a condom on. Since we play with them often, we've all thought about getting an updated STD panel and then having some bare fun with each other. My last check was over a year ago.
There are plenty of very safe ways to have sexual fun and limit your number of partners. That's one of the things that's positive about masturbation and porn. You can also meet people and do same room sex. It's like a live porn show with actors that really care about each other.