@aFFi : It's subtle, but Anjou has some heavily repressed self-esteem issues (hinted during the mirror scene in the flashback chapter).
In fact, what makes those two really interesting is that they're the opposite sides of the same coin. Seto has an inferiority complex and constantly tells himself that he's not worthy. Meanwhile, Anjou has more of a superiority complex (for lack of a better term) and overcompensate with an aggressive look and behaviour.
It's like she testing him to see how much she can tease him before he snaps and jumps her... but she clearly doesn't like lustful men.
It's flattering to her. She needs the validation and attention Seto provides when he get flustered by her antics. She already hinted that she thinks that it's "cool and manly" of him that he doesn't actually jump her (even though it's obvious he isn't indifferent).
Seto makes her feel safe. She can feel sexy and desirable without actually having to go any further. She can "be herself" with him, even though this "self" of her is a teasing and flirty attitude she uses to hide her own insecurities.
She's constantly insulting his appearance... but keeps helping and reassuring him in his efforts to better himself... and she's always praising him in some other way.
She's insecure. She doesn't want to admit that she's in love (see flashback chapter, again). She doesn't want to convey her love directly to Seto, probably out of fear of being rejected (because Seto WOULD reject her, since he feels unworthy). That's why she teases him like that and makes it seems like she's joking around.
She's working hard to stay physically close to him, always touching, always being sexy, always exiting, but she doesn't seems sexually attracted to him, like she's doing all that just for the tease.
And she seems to be running into him an awful lot... like a stalker would.
That's the big thing. Anjou actually needs Seto much more than he needs her. Just like Seto, she's flawed and needs to grow as a person. But while Seto acknowledge it and is already working on changing himself, Anjou is repressing her issues (check the mirror scene, once again).
I really hope the author is going to explore more of her psyche. She's a really interesting character. Like another author would have said : "One doesn't become a gal without reasons".