One who is hopelessly addicted to the massive online game, Runescape. "Filthy Runescapers" usually resemble a chubby, nerdy-looking boy. But beware, sometimes these super-nerds can appear in female form too. These "people" usually come to school ranting and raving with their nerdy friends on how they finally completed the "Trolls of Faramont" quest on Runescape the other night. Beware! If they get too close they may give you their Runename so you can chat with them, or even worse, invite you to play with them.
An unfourtunate encounter with a Filty Runescaper
Filthy Runescaper: Hey, you! Guess what?
You: You're a Filthy Runescaper, why would I care?
Filthy Runescaper: Because all of Valador trembles at the very sight of my dragon-skinned sword and Mithril long-range elf bow!