While our mind refuses to believe this as real, we’ve long resigned to the fact that human beings are capable of doing some very weird stuff in the name of just trying it out. Bagel head injections probably fall into the same category. Allegedly a growing trend in Japan is for people to have a bagel/doughnut style indentation on their foreheads.
For the process, the technician inserts a needle into the forehead of the subject to inject them with saline. They then use their thumb into the blob to create the desired bagel shape. This is only temporary though, and the body absorbs the saline in about 16 hours. Video of people getting injected in the forehead to make forehead bagels is right below.