After ceasing to wipe after you defecate, the act of progressively building up dried fecal matter around your anus forming a layer of "crust" in one's nether regions. Crustmaxxing refers to the highest layer of build up achievable by an individual.
Person #1: "I haven't wiped in 3 weeks"
Person #2: "Oh so you're Crustmaxxing"
The act in which a person attempts to meet all of their dietary and nutritional needs via the ingestion of exclusively human semen. Some have asserted that one would need to around 400 cum shots daily in order to survive. Contraptions necessary to achieve such cum levels require multiple men jerking off into a giant funnel and the cum recipient sitting or standing below the funnel.