DUDE I HAD THE EXACT SAME IDEA AS YOU!
I was actually in the process of writing on elike this, only I titled it
"Hatred on the Wall"
It's not done yet, and it's based more on the racial hatred that's often seen written there. I hate reading that crap.
The school newspaper brought up the problem of the graffiti and one sentence made me laugh.
"Honestly, no one cares who loves who, or which freshman is a slut."
Actual sentence. Made me laugh. But it's true!