Nat getting pounded has nothing to do with the foundations of the other routes. It's founded on the dynamics between Ethan and Nat and whether or not Ethan encourages Nat to get "pounded" or not.
With peter it's lacking any solid incentive from Nat to engage with this character. Peter being a creep and slowly trying to "corrupt" Nat would be more intriguing if it had a more solid place to start from, examples: peter gets injured and needs someone to care for him, Nat being out of a job and needing money takes this opportunity. Even if peter is lying about being injured and it's all a manipulation tactic to get closer to her, works both ways.
Or maybe if Peter was very rich and tries to sway Nat with his lavish lifestyle, if Nat is jobless and Ethan struggling at his job this would be a solid foundation for this arc. You see what I mean now?..Probably not since you have no grasp of the concept of foundation.
But hey, if you like this current version of Peter and think it is a compelling corruption story...good for you. As for your other comments, not only do they make you look like a teenage boy, they also shine a clear light on your insecurities, I don't really need to say it..do I?
Hold on let me put 3 emojis like you, for increased effect.