Name: Leliel, Angel of the Night
Classification: The Twelfth Angel
Appears in Episode: 16
Leliel is the Twelfth Angel, and is among the most interesting of the Angels. Its physical form is composed of two parts, a black spherical floating object and a large 'shadow' on the ground. However it is the spherical object that is in fact the Angel's shadow, while its main body is the 680 meter in diameter and 3-nanometer thick shadow on the ground.
While previous Angels used their AT Fields to repel or block incoming fire, Leliel instead uses an inverted AT Field to consume. Its main body, while only 3 nanometers in thickness, is an area of space that can only be characterized by abstract mathematics. Ritsuko Akagi calls this area a Sea of Dirac, which she suggests to be an alternate dimension or universe. It is by drawing objects into this area that Leliel proves to be an extremely dangerous opponent, consuming large portions of New Tokyo-3 and Evangelion Unit-01 itself.
The very nature of an inverted AT Field prevents Evangelion Unit-00 or Evangelion Unit-02 from attacking the Angel directly without being consumed by it.
Few details are available pertaining to the relationship between the Angel's main body and the spherical shadow it casts into the sky, however it is often described as a type of corridor that links the Angel's internal space to real space (this is based on the disappearance of the shadow when attacked). When the sphere vanishes, the corridor into its internal space opens, consuming anything that touches its main body. Thus Leliel's most distinguishing characteristic is that everything about it is inverted: its AT Field, its shadow, even its form of attack.
Following Evangelion Unit-01's absorption Leliel, the Human Instrumentality Committee and SEELE fear that the Angel may have attempted to make contact with the human mind, in this case Shinji Ikari, the Third Child and pilot of Evangelion Unit-01. This is indeed the case. While inside the Angel, Shinji is subject to severe psychoanalysis as Leliel attempts to probe his mind.
Eventually Ritsuko Akagi comes up with a plan to use the remaining two Evangelion Units to disrupt Leliel's inverted AT Field, while bombarding its main body with all 992 Nē Weapons remaining in their arsenal. This would hopefully kill the Angel and recover Evangelion Unit-01, though likely at the cost of Shinji's life. Despite Misato Katsuragi's objections, the plan is approved. Fortunately, it is never realized.
In what is considered to be one of the bloodiest and most disturbing episodes of the series, Leliel is destroyed by a berserk Evangelion Unit-01 as it literally rips the Angel apart from the inside. This happens only after Evangelion Unit-01 runs out of internal power while still trapped inside the Angel, leaving the pilot Shinji Ikari on the brink of death.