Fei: Cloud of Final Fantasy 7 is arguably the most popular RPG protagonist of all time. At the time of Xenogears's creation, Squaresoft, looking at its recent spiky-haired money-maker, must have mistakenly assumed that Cloud's success comes from his being immensely fucked up in the head, and set out to create the most screwed up, issue-laden protagonist of all time. Fei is the successful result of their endeavors.
Early on, Fei seems relatively normally psychologically impaired for a hero (does anyone else find it disturbing that such a significant percentage of our main RPG characters are at least a little unbalanced?). He's just a kinda pansy little whiner, really. "Waaaaah I dun WANNA pilot the big robot!" "Okay, pretty lady, go ahead and shoot me in the head. Nah, it's cool. I'm way too temporarily emo to care." "Citan, stop trying to get me involved in global affairs of extreme importance. I just wanna sit in the room at the inn and listen to the Cure, okay?"
However, as time goes on, we find out that he's actually got 3 people in his head who are all fucked up losers--one's him, one's Id (a thumb-sucking sissypants who thinks that being able to pilot a robot is the same thing as being powerful), and one's an addict to memory TiVo. Also, his father wants to kill him, while also helping him, because his father has been possessed by the ghost of the evil side of Fei in a previous life. Also also, he watched his mom erupt into a puddle of blood when he was 5. Also x3, he's the latest in a series of reincarnations of the same guy, one reincarnation of which was a deadbeat scientist pseudo-dad who went and died and left his creation-daughter fatherless, and now Fei has to deal with this problem that his former worthless self left to his current worthless self. Yet, in spite of all this, he seems to take most of this insanity in stride in comparison to his earlier angsting over the fact that people might want him to help them out so they don't all die in combat.
However, without Fei, there could be no scene in which Fei tries to catch that one fish, so in the end, he's still worth it.
Citan: "Hi, Fei. I know absolutely everything you want to know, but I am not going to tell you until at least 40-60 hours from now. In the meantime, have some Soylent Green."
Elly: Elly is a pretty pilot who is the 646th reincarnation of the mother of the world. However, no matter how many times she lives, no matter how many people throughout history she meets and influences, her taste in men never, ever improves. Also, she has parent issues, with her mother, and father.
Bart: Bart is a prince with one eye who is fairly happily engaged to a 12-year-old (and the worst part of this is that it's a way more believable and likeable relationship than that of Fei and Elly). Oddly enough, in direct contrast to the many potentially interesting but woefully wasted cast members succeeding him, Bart gets a ton of screen time to develop in, but in the end seems more like a vehicle for moving along the plot than an entity of any noticeable personality.
Rico: Rico is a monumentally important character with a significant past (involving his father) who is a valuable part of the plot.
Until you're done with his city, that is. Then he turns into a mostly-mute meat shield.
Chu Chu: Chu Chu is a talking cute fuzzy whatsit that can grow big. It tries to commandeer the plot for a few minutes in order to sneak in some development, but then a big robot beats it up for trying to be a real character.
Billy: Billy is a monumentally important character with significant issues involving his father who is a valuable part of the plot.
Until you're done with his 20 minutes of plot-forwarding, that is. Then he turns into a mostly-mute handgun.
Maria: Maria is a monumentally important character with a plot-significant heritage (involving her father) who is a valuable part of the plot.
Until you're done with her city, that is. Then she turns into a mostly-mute pilot.
Naw, just foolin'! She actually turns into a mostly-mute pilot even BEFORE you're done with her city.
Emeralda: Emeralda is part of the 2/3rds of the game's playable cast whose characterization is largely made up of what her relationship with her father was like. Her father being a scientist who is one of Fei's previous lives.
Deus: Deus is a big monster thing made to wage warfare on a planetary scale. The only specific power it possesses that the player ever sees is to create an insanely over-complex and ludicrous sequence of events over the process of millenia, including the actual creation of a human race, that will ultimately end with it repairing itself because it is so monumentally inefficiently designed that it can only be repaired by eating a shitload of zombies. I guess maybe somewhere in the future, gasoline becomes so scarce a resource that we start manufacturing devices that run on zombies instead because they're more plentiful than petroleum.
...maybe somewhere in the NEAR future, even.
Chair: Fuck Deus. THIS wooden horror is the true nemesis of every Xenogears player.