Searching for that kind of material is more about hunting through specific communities than just a bookstore. Mainstream platforms tend to sand down the rough edges to appeal to a broader audience, so the really gritty, authentic-feeling stuff about dorm life, awkward hookups, and all-nighters in the library tends to pop up in webnovel spaces or certain subreddits.
I've had decent luck on Archive of Our Own if you apply the right tags. Writers there often pull from their own college experiences, so the details about shared bathrooms, terrible dining hall food, and the stress of finals week feel lived-in, even when the plot gets spicy. The 'Alternate Universe - College/University' tag is your friend.
Don't sleep on forums for serialized fiction apps, either. Sometimes you'll find a story that's essentially a slow-burn romance with a side of academic probation, and the author clearly knows their way around a campus. The key is that the setting feels like a character itself, not just a vague backdrop for the steamy scenes.