Shy woman, sub with one lover, wants to play water sports but how???

I am 34 years old, divorced for 4 years now. I don't have kids, and I fuck a lot. I did before I got married (32 different guys) and after my divorce. I wasted no time, it was 2 weeks after my husband left that I let a male friend fuck me. I'd had 42 total men in these last 4 years. I finally realized, I was a slut, I was very whorish, and I let just about anyone who asked have sex. I sucked cock, let guys fuck and cum in my pussy, and even let the ones without huge cocks buttfuck me. I still wanted more. One of the guys I fuck sometimes now is pretty domineering. He wants to control, he's even tied me up, written things on me, last friday he walked in and with no preamble at all said "Bend over the couch, and lift your skirt, I'm gonna fuck your ass, I need to cum right now, then we can go to dinner". I dutifully bent over, lifted my skirt, pulled down my panties to my knees and grabbed some lotion and lubed my rear. I got buttfucked, he came, not caring at all about my orgasm or anything. It was rude, it was crude, it was all about him and I don't think my pussy has ever been that wet. We went to dinner with his cum up my butt and leaking out, my pussy was soaking my panties and when i got up to go to the ladies, I saw I had a wet spot on the back of my skirt. I was still soaking wet from being used like that, just "bend over" and get fucked, and up my ass as well. He isn't always like that sometimes he's very caring and a very good fuck, I cum like crazy and repeated times with him. He makes me tell him about the others that fuck me while we're dating. He likes that others fuck me. He has had me text him after I just got fucked and had the guy leave. This one comes over and fingers me while he sucks my nipples and tell him what the other guy did to me, then he mounts me and fucks me too.

A few of times he has written on me in black marker knowing I was going to see another guy right after and have a date, and go to bed with him. The other guys either laugh at it, or two of them fucked me then never saw me again. It's very embarrassing. This summer he bought me a barely there bikini in super thin white material. You could see the writing on my body at the pool complex. Then when I got wet, it was like I had nothing on at all. You could see my boobs, my dark nipples, and my trimmed black haired pussy, even the outline of my pussy lips, and my ass too. The thing is I want more of it. I want to be more submissive, I think I want to be like a fuckpig, cumslut for him, I want to be just a set of holes that he fucks and uses for his pleasure. I enjoy him being inside my body taking his pleasure. He leaves the door open when he goes to the toilet, and now makes me leave it open too. One time without wiping after poo, he bent me over and buttfucked me in the bathroom. I washed him and me off in the shower. Now I want him to pee on me. I want to ask but don't know if he'd like it or leave me. I want a man to piss all over my naked body, even in my mouth some to taste it. I want to lay down naked with my piss smelling body and have him fuck me. I think I even want to get him to piss on me in clothes, maybe even piss myself clothed in public while he watches. I just don't know how to say it to him.