This is a sex move performed by
two women. One woman eats nothing but cheese for many days and does not
poop regularly. Eventually, she allows herself to take a huge dump, and the two girls use the resulting turd, which is referred to as a bluntcake, as a double ended dildo.
To enhance the experience, sometimes the other chick eats nothing but
high-fiber-organic-angry-
lesbian-granola and Metamucil for several days and then has fucktons of explosive diarrhea, which they use as lube.
Another variation is Strawberry Bluntcaking, which is when one or more of the girls are on their period.