An interloper being someone who intrudes or meddles in a situation (inter "between or amid) + loper "to leap or run" - https://en.wiktionary.org/wiki/loper ), an extraloper would be someone who dances or leaps around the outside of a subject or meeting with similar annoyances.
Are you sure the extraloper doesn't just run away on tangents?
They run on secants towards the outside.
Wouldn't that be an exloper?
Edit: Geometrically, I agree an extraloper could run on secants (or radii) but they're not allowed to strike a chord.
But getting back to generative text, I feel that "tangent" is more appropriate ;-)