Philia - Role
Philia fulfills certain tropes in storytelling and RPGs, whether it be in typical Japanese storyteling fashion or just over-cliched RPG development. Not that these are necessarily bad, but it's fun to poke fun at certain things when you notice them. Here are a couple of things which may or may not fit Philia, but in the end you should realize that nothing about Philia really is cliche in the end because she has evolved into such an interesting character who stands out by her own merits.
The first thing a Tales fanatic (or RPG fanatic in general) will notice would be that Philia is, in fact, a priestess. Along with this archetype would be her fastidious or legalistic nature when it comes to morality in general, unlike other certain female priestesses such as Mint Adenade (Tales of Phantasia) or Ion (Tales of the Abyss; I know he's not a girl, but he fits the archetype), the grace usually accompanied with this trait is seemingly absent. Also, despite being a priestess, Philia does not have any healing abilities innate to her; then again, after Phantasia, the Tales series typically assigned the role of the healer to odd archetypes (in Destiny, it's the thief Rutee. In Eternia, it's the fist-fighter Farah. In Symphonia, it's the teacher/nerd Raine.).
Philia is a Megane-ko, which automatically makes her somewhat of a nerd (or a mild form of a Gadgeteer Genius); even though she has Clemente, Philia also relies on hand-made bombs to aid her in battle and has a variety of support skills, such as identifying an enemy and such. A few other nerd-type characters in the Tales series include Claus from Phantasia, Keele from Eternia, Raine from Symphonia, and Will from Legendia.
Yet another aspect of Philia's role is that is that of the second love interest. Although it's canon that Stahn and Rutee end up together (having a kid who's the star of Tales of Destiny 2 and all), Philia reveals at one point that she has romantic feelings for Stahn. In the Tales series, there aren't very many third-wheel characters in terms of the canon pairings. However, there are a select few; there's Sheena, who's a possible romantic interest between Lloyd and Colette in Symphonia, and Chloe who definitely has feelings for Senel despite Senel's main potential being Shirley.
Oh, and let us not forget the most obvious role; that of the magic-casting powerhouse of this Tales title. Once Philia wields Clemente, she slowly but surely gains numerous powerful magical spells. Of course, Clemente being the Lightning Swordian, she also has access to one of the most well-known Tales spells: Indignation. Other mages in the series include Arche from Phantasia, Keele and Meredy from Eternia, Genis from Symphonia, Grune from Legendia (okay, okay, maybe Will and Norma, too), and Jade from Abyss.
One thing which is very interesting (to me, at least), is how much in common Philia has with the Tales of Vesperia heroine, Estellise Sidos Heurassein. Both characters, until the events of their respective games, have been isolated in a remote place (Philia in the temple, Estelle in the castle) and have only read about the outside world in books. Both also have a fastidious nature; in the beginning of the game, Estelle is opposed to such actions as breaking and entering (though, traveling with Yuri, she quickly just shuts up instead). While they do have their differences, it's almost as if Estelle is an expy of Philia. Of course, since Tales of Vesperia is the tenth anniversary Tales game in North American (with the first being Tales of Destiny), it's not completely out of the question.
In short, there are several roles which Philia fulfills in Tales of Destiny, and it's really interesting to see how these aspects of her character are carried throughout the entirety of the Tales series. However, what's even more amazing, really, is how Philia takes all of these traits and becomes a very unique character all in herself.