In the Medieval Ages there was a period when bakers began cheating the public at such a rate that public outcry reached the ears of several kings. As bread was a daily staple of Medieval life, the bakers knew that they could charge a lot of money for minimal portions of their products. As such, kings levied laws against bakers stating that they were to lower their pricesand keep honest. In fact the common term "A Baker's Dozen" (meaning 13 instead of 12) came from this time period. Any baker caught selling less than an even dozen was strictly and harshly punished. As a result bakers began adding one extra loaf to be certain their count would be correct or even over the amount decreed by law.

When someone goes to the gym and spends 90% of the time on their phones scrolling through social media

Thirteen(derived from devil's dozen where baker=devil)

When a baker slips you an extra egg.

Sexual intercourse involving 12 men and one girl which includes fucking her vagina, ass, mouth, tits, hands, chin , feet and back of the knees. At the end she should be sprayed with a fountain of cum causing her to drown.

A Bakers Dozen is a recent Marine Corps tradition in which 13 people evacuate their bowels into one toilet consecutively without flushing. Can be a highly effective corrective measure, but isn't always done for any particular reason. As all things in the Marine Corps, the Bakers Dozen must be executed with the utmost professionalism, integrity, and attention to detail.

A saying used to describe an obese person whose layers of fat seem to cause "13 rolls"