A generally unattractive Ichabod Crane/Olive Oil looking person, gangling in appearance, with a face that suggests mild retardation.
"Look at stretch over there."
"Poor lerp must have a hard time finding clothes that fit."
Lerpes manifests itself like herpes, however it is only contracted through close contact or the "bumping of uglies" with a lerp. The resulting pustules can appear anywhere on the body.
Did you see that fugly guy Tanya took home last night? That bitch is gonna catch a mad case of lerpes.