Raider Rash is a slang term for STDs; since Texas Tech University is known for its high STD rate (one in four people have STDs at Texas Tech,) and its mascot is the "Red Raider."
Kristi got drunk at a party; then she decided to have unprotected sex, and now she has gotten the Raider Rash.
Raider Rash is strand of STD's which comes from Lubbock, Texas. The disease is airborne but can also be contracted from bestiality (or similar animal looking creatures). It has side effects of painful urination, pustules around the genitalia, denial (see above), and will decrease GPA to a 1.0 which is still above average at the University of Texas Tech. The only cure is to quarantine infected areas (Lubbock) from the rest of the world.
Guy 1-"Hey do you want to go to Lubbock this weekend?"
Guy 2-"No, you can get Raider Rash by just being in their presence."
Does not exist. Its a rumor that started because people will believe anything they hear. Texas tech STD rate is about 5% a year which is consistent with all the other Big 12 schools.
"Did you say Raider Rash? Come on man that shits not true."