Peyronie's disease is described as fibrous scar tissue inside the penis that causes curved, painful erections.
Jelqing is a natural technique that enhances the penis size. Described as a form of "milking" that improves blood pressure and circulation. It is performed by repeatedly stroking the penis in a squeezing motion from the base of the shaft to the corona of the glans. This video shows a 'clean' demonstration of the Jelqing technique. https://www.thebathmate.com/max-out-jelqing-serum/