Silverstone disease

Rena Hirose in her space suit, designed to protect her from sunlight

Silverstone disease (シルバーストーン病 Shirubāsutōn-byō), officially known as Congenital E-Irradiation Syndrome (先天性E照射症候群 Senten-sei E shōsha shōkōgun), is a rare skin disease in Strangereal. The disease prevents a human's skin from protecting the body from E-rays present in sunlight, which can lead to death by radiation. It was named after Dr. Antonio Silverstone, who discovered the disease.

The only known sufferer of Silverstone disease was the ace pilot Rena Hirose, who wore a specialized space suit to protect her body from the Sun's E-rays.

Trivia

• Silverstone disease is similar in nature to Xeroderma pigmentosum (XP), an actual skin disease that prevents the skin from repairing damage caused by UV rays.
• In real life, E-rays are actually extraordinary rays, which are one result of birefringence, a property that results in double refraction when an object is viewed through a birefringent material (for example, a pencil in water appearing as though the pencil is broken). Whether an affected ray of light is ordinary (o-ray) or extraordinary (e-ray) simply depends on the light's path, and e-rays bear no harm to the viewer.