Samurai Elf, or Gekka as a companion, is a monster in the second part of Monster Girl Quest: Paradox.
Monsterpedia Entry
Attacks
Strategy
Evaluation
"To have your ass raped and be raped by asses... You sure are versatile. A hero who enjoys being reversible. That is you. The Samurai Elf uses very powerful Sword skills. If you fight her appropriately it shouldn't be too hard. Because she's a warrior type she's weak against Pleasure attacks. Confusion and Blind can be easily applied so make good use of them. Now go, oh Reversibluka. Next time you lose, you'll either have to kill yourself or have sex."