You guys want to know what shaving cream does to automotive paint? It bleaches it.

When I was in grade 7, a bunch of girls in my class got some cans of shaving cream, and wrote "Grad 88 rocks" on our teacher's car. It set for an hour, maybe two. Our teacher got out there, saw it, and lost it. Even after sitting on there for as short as it did, you could still see the words in it a year later.