Even if you try to go with a "good" route, you are still led down the story path.
- If Lucy avoids drinking, dancing on the table, or flirting, at the sorority house she will get pulled aside and told she's very close to not making it and will be booted from the process.
- Ryan still gets excited, corrupted or not, knowing that guys are into Lucy.
- Lucy still goes to the club to be a club girl, and even if you try to be reserved she still ends up being a lot more intimate than a loyal/pure route would facilitate
- Even if you don't get the Ryan Corruption flag set, after the club he still wants all the details about how the guys were acting around her.
So I don't think there'll be much of any sort of loyal/pure route. As the game revolves around the sorority, not getting into it would be expected to lead to a game over.
On a completely different note, I personally hope the game stays away from forced content. She's naturally finding her own curiosity and is opening doors herself to a whole new world. I really like that the player can control how it proceeds. Will she corrupt Ryan? Will she actively flirt at the club? Will she swap numbers with other guys, and if so which ones? Will she send selfies to Ryan? If the dev lets the reader continue to choose how/when she opens her and Ryan's own doors and windows, my interest will definitely continue to rise for this game.