The question I have from your post is whether Chad only entered into a relationship with Sage so that the straight jocks could get access to hot pussy.
The impression so Zoey only had sex with the MC before she left for San Diego is just an impression.
With Isabella, he just didn't detail the earlier sexual debauchery because there was no need for it. Isabella is/was married. Sage and Zoey are older than the MC and both like sex with guys. Therefore, it is unlikely so they did not have sex with other guys before the MC. Sage may have even had sex with another guy before Chad. But again, there is no need for DPC to show us that. Actually with Zoey I think even so we as players decide if there will be another ex besides the MC. We have a choice in Interlude between fucking the MC or exploring each other's bodies.
With Josy, it's really vague. On one hand she fucks the MC's cock like a world champion, but she has no real experience as far as blowjobs, breastjobs and assjobs go. That actually points to excessive dildo play for me. To make matters worse, in order for us to have a proper flashback of Josy and Maya, the first time they had sex together and both were still in high school at the time. So just 18 years old and we learn in EP2 from Josy herself so she hasn't had human contact in months. It's all kind of contradictory.
There's supposedly a tradition of the HOTs and Alphas partying together. If it's just been for a couple of years, it's not much of a tradition, so I don't think Chad started dating Sage to make that happen. More likely he used Sage to hide his homosexuality, especially since the company he keeps are likely to be homophobes.
I don't take Zoey's words to mean she's got a lot of comparison, but she simply gets turned on by the mc.
The back story with Zoey and the mc, how they used to hang out, is probably out best clue:
mc: "But I got my punishment for standing up for myself. Detention."
mc: "Every day for two whole months."
mc: "And that's how I met her."
mc: "Zoey."
mc: "She was a bit like me. An outcast."
mc: "That's probably why we got along so well."
mc: "Zoey was in detention for smoking during class..."
mc: "...that pretty much sums her attitude up."
mc: "Her looks were...rugged... That's not a word usually used to describe a girl...but she was."
mc: "She wore dirty clothes, her hair was a mess and she had a self-pierced nose."
mc: "We were the only ones in detention."
mc: "And the supervisor just left us alone for most of the time."
mc: "So, naturally, we got to talking."
mc: "By that I mean, she talked and I listened."
mc: "She became my first real friend."
mc: "A girl as a best friend."
mc: "Zoey taught me a lot of things..."
mc: "Like how to smoke and stand on a skateboard."
mc: "I didn't like smoking and my balance wasn't meant for skateboarding..."
mc: "...but I blindly did those things..."
mc: "It was always fun being with her."
mc: "As we grew up, our...pastime activities...changed..."
mc: "She had a friend with an older brother who would buy them alcohol."
mc: "She would share it with me..."
mc: "And one night, we were partying together in a tree house."
mc: "I don't even remember whose tree house it was...but we were in it...drinking and having a good time."
mc: "At one moment, our eyes met and there was this awkward silence..."
mc: "For the first time in my life..."
mc: "I got kissed."
mc: "My best friend, for all those years...kissed me."
mc: "Our relationship shifted...from being a friendship..."
mc: "...into something more."
mc: "We had no clue what we were doing. At first, we thought it was something fun to do while being drunk."
mc: "But then we started doing it when we were sober."
mc: "And it also led to more than just kissing."
That reads like they both had their sexual awakening in that treehouse to me.
Regarding Isabella, I'm sure she fucked her husband, and that she fucked a lot before then as well.
Josy probably also had some sexual relationships, but probably nothing serious. It's likely she'd fucked some dudes during highschool, but DPC isn't gonna get into that, since that's not the appropriate age group to be depicting sex.
Not yet, last post was on Saturday.