In November, Marc Jacobs was featured in a South Park episode as shirtless action figure "Muscle Man Marc," so it's only fair that Jacobs repay the tribute and feature a nude Eric Cartman on a t-shirt created to benefit The Interdisciplinary Melanoma Cooperative Group at New York University.

Randy Marsh, Butters Stotch, and Eric Cartman have replaced the likes of Naomi Campbell, Victoria Beckham, and Chloe Sevigny in the designer's latest campaign to fight cancer in partnership with NYU's School of Medicine. Emblazoned with the words "Protect Your Largest Organ" (an organ that Jacobs loves to tan), tees are available for $35 online and at Marc by Marc Jacobs boutiques nationwide.

The Marc Jacobs show this Fashion Week will close out the catwalk season (again) on Monday, and chances are you're not invited... but now you can make a splash amongst the fashion set this week donning a cardinal red t-shirt silkscreened with a naked cartoon character holding his testicles.