Utena's been invited to a duel! How nice!
A while after, a card is send to Utena. Written on it is "To the one engaged: I shall wait for you at the Duel Arena this evening."

Utena and Anthy.

When Utena arrives at the arena, she is surprised to see one of Nanami's lackies there. She doesn't even know her name. Plus, the desks in the Arena all have umbrella's on them. We can guess why this is so.

En garde! ] And she attacks!  My, what a fierce battle...!!

So, Utena draws the Sword of Dios from Anthy after Keiko challenges her, and begins the duel with Keiko, who has Touga's sword to duel with. She claims it is the "noblest sword in the world". While dueling, Keiko keeps on screaming her lungs out, saying how she is going to kill Nanami so she and Touga can be together. She even says that Nanami, not she, is the troublesome insect, the negative element which stands between her and her love.

She takes a breather.  Ready to go again! 

Transparent Period of Adolescence (1.6 MB) - Keiko's duel song. Got it thanks to Gio!

Utena: "Why are you..."
Keiko: "You should know well what kind of a girl Nanami is. She doesn't even think of a girl like me as a person. Knowing that, I've been serving her anyway."

Here comes Utena!  The rose...  Keiko lays, unconcious...

And the duel goes on, until Utena defeats Keiko (surprise, surprise). The troubled girl falls to the ground, unconcious, just as all the other Black Rose duelists before her did.


Utena: "I don't even know her name. I thought she was Nanami's friend. It's scary how the roots of one's hatred spread underground, unseen."

Boy, can she ever fake happiness.  Together again. Blah. 
"I'm happy only being with you, Nanami-sama. There's no way a girl like me can love Touga-sama, is there?"

Next time we see Keiko, she's back with Nanami, Aiko and Yuuko, with no memory of the duel whatsoever. But, one can ponder, how and why can she go back to Nanami after all that girl's done to her? One word: Touga.

Hm, Utena doesn't get it.  Happy, happy... 
Anthy explains to Utena.  ...and Utena seems somewhat shocked. 

Utena: I just don't know...
Anthy: The one with her hair tied and her bangs curled is Keiko-san. The one with shoulder-length hair curling to the outside is Aiko-san. The one with her hair curling to the inside around her cheeks is Yuuko-san.
Utena: That's not what I'm talking about. How can she still be Nanami's friend? Even though she's actually carrying all sorts of feelings...
Anthy: For someone you love, your feelings for any other people become insignificant. You can deceive yourself as much as you need.

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