I've written myself into a corner and need a nudge (or four) in the proper direction. The end result of this conflict will be our young hero leaving his current sanctuary and the end of Vol. 1 of 3. The catalyst is an outdoor party, teenagers around bonfire, home-made hooch, etc. etc. We find the hero drunk for the first time ever drowsing on a bench by the fire. The party has moved on the local swimming hole without him. Best friend/roommate comes to the rescue and as our hero blearily watches he realizes everyone's naked. Our hero becomes aroused in his drunken stupor watching nude swimmers frolic and fails to notice roommate's naked girlfriend come over to assist him in the water. Picture a stout blonde farm-girl of Nordic extraction. She hoists him aloft to aid in disrobing, notices his obvious arousal and one thing leads to another. One thing being an innocent but public and premature ejaculation another being our hero spews his previously-consumed adult-beverage down the front said girl. He staggers home in abject humiliation. Day two. Hero recalls nothing. Girlfriend starts smear campaign alleging outright perversion. Roommate understandably pissed...
Subplot to what? Parents can be subplot. A newly arrived cousin can be subplot. Neighbours. Secret crush. A freshly arrived exchange student. I'm not sure what you're asking. If you want suggestions about what happened the day after, that'll be continuation of the main plot, not sub.
Perhaps I'm confused re: subplot...I thought the hero's journey the plot, the roommate and his GF's relation and how they effect the story a subplot?
No anything that directly effects the main character in real time is the plot. Subplots often involve side character stories that seem unrelated to everything else that's going on but eventually tie back to the main plot. So if the girlfriend's bf was searching for her long lost brother and it turned out to be the hero and she makes the girlfriend see the hero in a different light. That sort of thing.
Now you could have the main character finding out that something he did last night and can't remember caused he's roomates and his girlfriend to fight badly, maybe they even broke up because of it.