While there are lots of wonderful female characters out there, I will have to stick with Satsuki from Glass Heart Princess for now. Just how often do you find a stoic, but hilarious, character like her? This post contains moderate spoilers of the game, mainly of Shinnosuke's route.
Sometimes, when I'm in the middle of playing an otome game, I find myself stressing over nothing. I feel frustrated upon, say, watching how tiring or shallow the plot is. Often times, I find myself raging over how disappointed I am with how the producers of the game portray the so-called "typical shoujo interactions," which involve the girl avoiding the guy for trivial reasons or for no legit reason at all (e.g. "I'm in love with XXX! What should I do? First thing first... I have to avoid him!").
Satsuki, however, stands out although her role can be pretty much be described as minor. Even though she is just a maid, she is direct, sarcastic, stoic, but loving as the same time. Being as stoic as she is, she makes fun (in a loving way) of Kyouko's attempts to fall in love and even Shinnosuke for being a pretty much a hetare as he is. She doesn't pursue personal gain in doing so. She stays herself from the beginning up until the end because all she seeks is personal entertainment. Which is also why she doesn't get swayed by the situation or second-question her decision and beliefs or whatnot.
She also shows strong bonds with Shinnosuke. They have been living and working together for quite some time, which makes it natural for them to understand each other more than anyone else. At some points, even Kyouko, Shinnosuke's love interest, or Shinnosuke himself. It doesn't mean that they have anything funny going on (I kid you not, I actually ship these two in the background), it just means that they have another unbreakable
bromance bond which allows them to stand by and support each other during hard times.
They are in sync, and Satsuki is actually the one who is able to open Shinnosuke's eyes (and make him realize how he truly feels about Kyouko) and fully support him until the end (if we look beyond her sarcasm). She may not look like it, but she always tries her best to protect the people she cares about.
Another distinguishable characteristic of hers? She's an open otaku. Sometimes I vision her as my representative during the gameplay. Her hobby and presentation of it makes her sooo much more alive and interesting than the other characters to me, even the love interests. If she was a guy, I'd go after her first for sure.
Although she appears emotionless most of the time, she shows her emotions every now and then... especially when it comes to the things she loves (e.g. she freaks out when adult Gai threatens to destroy all her collections). She has dark humor that sends me flying at times too.
In all honesty, Satsuki is a figure I'd love to see more often in otome games. She will remain on my top list of favorite female characters, and I'd rather see her instead of a bunch of annoying and violent fangirls whose behavior can send a thousand tables flying. She is one of the reasons why I enjoyed the game a lot, and she is much more than she is actually credited for. Did you see how wonderful she looks in a butler suit?