Rocky Mountain Butt Disease

A disease mostly affecting people from tropic and sub tropics environments, RMBD is contracted when one of these people attempt spending a winter in the Rockies, and then end up staying indoors for 5 months. Symptoms include, but are not limited to, an increase in waist size, and a much larger gluteus maximus, pale pasty skin, and a smell of poor hygiene.

Jane moved here last summer from Cali and ended up catching Rocky Mountain Butt Disease.

Butts disease

A rare but super contagious disease that spreads from birth.
If your parents had a butt then you unfortunately are a carrier for Butts disease.

Some symptoms include a rash and an irrational fear of the cold.

"what's this itchy rash from?"
"oh shit, I think you have butts disease!"
"damn. That explains the butt"

Iraqi Butt Disease

Severe Diarrhea that can also come with extreme nausea, shivers, and fatigue.

My buddy can't come tonight he's got that Iraqi butt disease.