A form of temporary body art called a “Bagel Head” is becoming popular in Japan. To get the look, saline is injected into the forehead until it swells into a circle. Then someone has to press it in the center to create the “hole” of the bagel. The process takes two hours but lasts up to 24 hours until the body absorbs the saline.
If you can stomach it, check out this video of some people get their bagel heads done: