Grue

A grue, as mentioned in Strip 201 by Largo, is a creature from old full or partial text based games such as the Zork series. Since grues only came out when it was too dark to see, no one can describe them. For years grues have been used widely in jokes on games or stuff relating to games, mainly mentioned involving dark places. Since Largo is under the trash and unable to see, a tingling in his toes might tell him that a grue is attacking since he often can't keep reality and fanatsy seperate. This tells us that Largo has/does play text based games.

See also: Grue on wikipedia.org