The Lack of Understanding.

Matthew Harrison, who prefers to be called Harrison due to bad past experiences, judges people by their looks. Not only does he judge people by the way they look, but he judges everything by the outside. He'd rather walk along the length of a beach than explore the water, and stay on the coast of a country and delve deeper into the midlands.
He collects a mildly attractive groups of friends but he never learns anything about them, and he doesn't know much about himself either. Until he meets a mysterious girl under unusual circumstances who crosses boundaries and intruiges him, and for the first time in his life her 'perimeter' doesn't seem enough.