Nearly nude metro Detroiters braved the cold for a good cause at Cupid’s Undie Run [NSFW PHOTOS]

Cupid’s Undie Run is a national charity event that sees participants strip down to their underwear to help raise money for neurofibromatosis research. The Detroit event was held on Saturday, a mile-ish run that started and ended at downtown’s Tin Roof bar. Neurofibromatosis, or NF, is a genetic disorder that causes tumors to grow on nerves throughout the body and affects 1 in every 3,000 births. Funds raised will be used for research through the Children’s Tumor Foundation.