Innocentius Summon

By that point, Kamijou Touma had walked right up to Stiyl.
With one more step, he would be close enough to punch the magician.
“MTWOTFFTO. (Manifest one of the five great elements from which the world is
constructed.) IIGOIIOF. (It is the great outset, it is the original flame.)”
An unpleasant sweat started flowing from Stiyl’s entire body. This was because the
creature in a summer uniform before him had taken the form of a human. Stiyl’s spine
trembled as he got the feeling that inside that boy’s skin was not flesh and blood but
some strange oozing something.
“IIBOLAIIAOE. (It is born of life, and it is the arbiter of evil.) IIMHAIIBOD. (It is mild
happiness, and it is the bane of death.) IINFIIMS. (It is named fire, and it is my sword.)
ICRMMBGP! (I call thee into reality, masticate my body for great power!)”
The chest of Stiyl’s priest’s habit swelled out and the power from within popped off the
buttons.
With the roar of flames sucking in oxygen, a giant mass of flames shot out from within
his clothes.

It was not merely a mass of flames.
The crimson burning flames had something black and dripping like fuel oil at its core. It
was in the form of a human. The thing was reminiscent of the seabirds dripping with
black fuel oil after a tanker accident and it was eternally burning.
Its name was Innocentius. Its meaning was “I will surely kill you.”

- Toaru Majutsu no Index Volume 1, Chapter 1 Part 6