“—Found you.”

They could hear a woman’s voice.

The problem came from within the wall that’s empty.

Kamijou turned around, and was momentarily stunned. At approximately his eyes’ height, there was tea-colored mud that was as big as a palm. It looked like chewing gum that had been spit on the wall.

And right in the middle of the mud was a human eyeball.

The eyeball acted like a camera lens, moving continuously.

[...]

Kamijou was unable to tell where the mysterious invader was, and he had no idea whether the mysterious block of mud was of esper power or magic.

But Index said without hesitation,

“A human image that’s made from dirt—this spell that’s interpreted from the Kabbalah is similar to those that we Anglicans use, especially the Jewish guardian stone golem that was forced to be a guardian angel of England.”

[...]

“It was said that God created humans through dirt. The stone golem is the end product of this theory. This magician must have created a stone golem that focuses on the eyeballs in order to search and monitor. Normally, the caster can only create one such stone golem, but if there’s only one eyeball, the composition to create a stone golem will drastically decrease, allowing the caster to create even more of it.”

Toaru Majutsu no Index vol.6 ch.2 pt.8