Posting from mobile. Apologize for errors.

This is a mix between an observation, report, and a question all bottled into one. Veteran answers only please.

I'm trying to figure out what's happening here. The good thing about TRP is you get to read stories an analyze them and apply it to real life. So someone please help me out here because I'm stumped.

 

I first met Tina (none of these names are real) at a gym I used to work out at and she introduced me to her boyfriend, Fred. Tina and I get pretty cool but she starts sending me IOIs. Me trying to salvage what little of a conscious I have left, don't move on it at all. Of course she starts to send nudes and so forth and I mostly ignore it. About a month later she asks me to come over for a bond fire. Who turns down a bonfire? Not me. I get to her and Fred's place at night and Fred heads in for a short shift at work. Three girls show up and we all start drinking. One girl sits on my lap and we all have a good time. Fred comes back and the three girls leave and two more show up. Body count: Fred, Tina +2 girls. We go inside, keep drinking and start to dance. I sit down pretty tipsy (That's a lie I was drunk as shit) and one girl gets on top of me and I see Fred, Tina and the other girl go in the bed room and shut the door. So now I have questions because wow I ain't neva seen no shit like dis... Wake up the next day head home had fun yadda yadda.

 

Yesterday I get another text. Bonfire. Oh hell yes. I'm there. Get to their place at night and Fred is at work. The girl who went in the bed with them during my last encounter is in the kitchen cooking. So I'm not sure what kind of thing they have going on over here but I'm down. I start playing portal 2 (great game) on PS4 and another girl comes to the house. We start taking shots and she's giving me IOI but then started talking about her relationship history. Fucking train wreck. I go out to the couch to chill and Tina and the two other girls end up passing out in the bed room. I chill on the couch since I'm hanging for the weekend. This morning Fred comes home from work and has yet another girl with him. He lays down on the couch as any man would after working all night and the girl gets on top of him and falls asleep.

 

So basically I'm just sitting here trying to figure out exactly what in thee fuck is going on. Someone is doing something right but I can't tell if it's Fred or Tina. Part of me wants to stay and part of me wants to nope the fuck out of here because there is some serious shit going on in this house.

TL;DR May have ended up in some type of swinger/orgy/sex trade clusterfuck of casual sex.

What kind of relationship is this? Is it objectively possible to have a LTR and plates? Who is the main benefactor here?