Heaven’s Gate

Heaven's Gate is an angel in the Navel of the World. Originally a Cherubim angel, she was ordered by Ilias to assimilate into the gate to heaven in order to prevent intruders from accessing the gate, whether from the surface or from the heaven.

Monsterpedia Entry
"A huge angel that is herself the Gate to Heaven. Originally a Cherubim, she was assimilated into the Gate, and ordered to guard it by Ilias herself. rather than prevent surface dwellers from getting into Heaven, her true purpose was to restrict angels from freely being able to reach the surface world without Ilias's permission.

''She was granted free control over devouring any who would attempt to unlawfully pass the gate, and render judgement as she saw fit. Since she is easily bored during her eternal duties, she would violate any trespassers for an eternity."''

Attacks
Seraphic Blowjob: Normal attack.

Male Teasing Tentacles: Normal attack, hits twice.

Great Gate's Lusting Tongue: Normal attack, hits twice.

Gate of Judgement: OTK, requires having Slyph active to avoid.

Battle Overview
Not to hard, summon both Slyph for offense and dodge her Gate of Judgement, and Gnome for defense. Use Salamander for extra SP to fuel Elemental Spica, or simply normal attack her to death. As long as you keep all spirits up, you are not in danger.

Evaluation
"To think you would even be raped by the gate... You manged to surprise me... Surprisingly. ...Though I made that gate, so I knew it was possible. Your enemy is an angel, so fallen angel dance is useful. Gnome will also help with defense, of course. Undine isn't as effective, so you can skip her. Now go, oh brave Luka. I want to use that gate again, so don't break her too badly."

Trivia

 * Her form while closed is most likely a reference to the sculpture "the Gates of Hell" by French artist Augustine Rodin (if that's truly the case then the tremendous amount of irony is obvious here).