Crossdressing!Anna (aka Andrew Wellum and trap!Anna) is played by Isadora. Actual, better wiki article later.
YOU PEOPLE NEED INFORMATION AND I'M LAZY, SO HAVE CHAT EXCERPTS OF ME EXPLAINING TO TARDY MY CHARACTER CONCEPT:
IsadoraTheGreat: let me start by saying I have a ton of different theories on how Anna and Kratos got together
IsadoraTheGreat: It's like a hobby, thinking them up
IsadoraTheGreat: There was this one time I was thinking:
IsadoraTheGreat: "Hey, wouldn't all the Desians be looking for Anna after she escaped?"
IsadoraTheGreat: "HOW WOULD SHE HIDE HERSELF?"
IsadoraTheGreat: And then some part of my brain went:
IsadoraTheGreat: "SHE SHOULD CUT HER HAIR AND DRESS AS A GUY"
IsadoraTheGreat: "FOR THE LULZ"
IsadoraTheGreat: And Kratos would know she's really a girl and pretend not to know
IsadoraTheGreat: BUT HE KNOWS
IsadoraTheGreat: Kratos runs into her just as she escapes wearing a cloak
IsadoraTheGreat: and his thoughts are "Hey pretty girl -WHY IS SHE RUNNING FROM ME"
IsadoraTheGreat: And she hides in an inn in Asgard, cuts her hair and walks out in boys clothes with the new name of Andrew .... something
IsadoraTheGreat: and at the same time Desians are handing out wanted posters and Kratos sees them and he's all
IsadoraTheGreat: "... Wasn't that the girl I just met?"
IsadoraTheGreat: "she's important to the organization"
IsadoraTheGreat: "i better hide her to cripple them"
IsadoraTheGreat: "yup, that's the only reason I want to help her :|"
IsadoraTheGreat: After that Anna's all "La-dee-da I'm a boy" and Desians come up and go "HEY DO KNOW THIS GIRL?"
IsadoraTheGreat: "N-no ..." *rubs GLOVED hands nervously*
IsadoraTheGreat: Desian: "... Why are you wearing gloves?"
IsadoraTheGreat: "It's SUMMER"
IsadoraTheGreat: Anna: err....
IsadoraTheGreat: SO RANDOM DESIAN # 12 rips off gloves and goes "HEY WE GOT AN ESCAPED PRISONER"
IsadoraTheGreat: "NOT THE ANGELUS PROJECT 'CAUSE THIS IS OBVIOUSLY A GUY"
IsadoraTheGreat: "BUT WE STILL GOTTA TAKE HIM IN"
IsadoraTheGreat: 'cause he sees her exsphere
IsadoraTheGreat: BUT LITTLE DOES DESIAN # 12 KNOW THAT KRATOS HAS SECRETLY BEEN WATCHING THE WHOLE TIME
IsadoraTheGreat: AND HE COMES TO KICK ALL THE DESIANS ASSES
IsadoraTheGreat: and Anna thanks him and introduces herself as Andrew and Kratos is in his head going "I KNOW YOU'RE A GIRL"
IsadoraTheGreat: and they run off to have lulzy adventures, idk
- Anna got her new last name accidentally when the Desian questioned her. It went something like -
DESIAN #12: So, Andrew, what's your last name?
ANNA: Well ... um ...
DESIAN #12: Andrew Wellum, right, got it.
- Anna feels her parents' deaths could have been prevented if she wasn't a girl, so now she has given up everything, including her gender, in order to exact her revenge against Kvar. That is her primary motivation for becoming a guy - the second reason is to hide from the Desians looking for her.
- Kratos takes on Anna as his apprentice for various reasons:
a) She asked him to teach her how to use a sword.
b) He knows she's the Angelus Project and decides that it's best to find a place to hide her, to keep her out of Cruxis' hands. Having her within eyesight until he does is only common sense.
c) In her rage for revenge, he sees himself, Yuan, and Mithos as they were after Martel's death. He doesn't want that same feeling to consume Anna as well.
d) Noishe whined a lot until he said yes.
e) He may have maybe, kinda, sort of already liked her as a person just a little, tiny bit by the time she asked.
- Kratos never bothers to tell Anna that he knows she's a girl until several months, possibly years after they meet, believing it wasn't really necessary and it was safer in the long run. He also felt she might not be as comfortable with him if she knew that he knew that she was actually a girl.