Eyeball tattoos because YOLO!
An eyeball tattoo is performed by injecting ink under the surface of the eye to change the color of the whites of the eyeballs. The pigment is trapped under the sclera, where it remains mobile and slowly shifts and migrates around the eye.
As with many heavy modifications, very few artists are skilled enough to perform eyeball tattooing safely. The following is an excerpt on the history of this procedure from The Eyeball Tattoo FAQ by Shannon Larratt on news.bme.com:
The injection method of tattooing eyes was invented by Shannon Larratt and first performed July 1, 2007 by Howie (LunaCobra.net), who has continued to develop and refine the procedure since. Shannon’s ex-wife Rachel had gotten an eyeball implant by Dr. Gerrit R.J. Melles in The Netherlands, one of the developers of the LASIK procedure. He had developed a method for inserting thin platinum jewelry underneath the conjunctiva, rationalizing that it would be safe because the eye has evolved to tolerate calcium buildup in this layer as people age. The implant was inserted by injecting a small drop of saline in order to create a pocket for the implant. Shannon theorized that the saline could be replaced with ink in order to dye the white of the eye and approached Howie about doing the procedure. After performing this procedure on Josh Rahn and Shannon Larratt, as well as attempting a traditional method eyeball tattoo on Pauly Unstoppable, Howie went on to perform the procedure on many others, refining it with an eye to efficiency and safety.