Crits~
Approval pert-
Is there any particular reason she needs to hide her actual age? A student can be theoretically 10k+ years old but so long as they really are considered mentally teen range then it's fine. The word usage only implies she's mentally a teen and by implying it gives the impression that she in fact isn't..a teen.
Her reason for enrollment is..valid but highly convoluted.
"
Shenny is fast, and fierce. And clearly, she loves fighting: in the middle of the battle she feels herself as a fish in the water, the madness around is her natural and comfortable environment.
Though, as any person of the same kind, she would love to become stronger seeking better opponents. So,
being clever enough, Shenny realizes she still needs training and learning, learning how her inner powers work, and how to control them, in the first place. Also,
being passionate enough, Shenny desires communication.
Being quite fragile inside, she needs people to talk to, as well as love, tender, romance, physical intercourse: everything other beings are up to."
Mostly it just espouses all these things she's apparently really good at and have a jumble of reasonings that follow no clear pattern. If she wants to get better then just say 'She wants to master her powers', if she wants to make friends then say that. By adding so much flourish I'm not sure what her real goal is and by that standard, I don't know really why she's enrolling.
FEAR- There is a lot of really... distracting information here. Both as a player and a GM. You want to be able to look at a FEAR attack and get what the attack is, and a very brief description of how it looks/works for your character. The more doesn't equal better rule. If you have a flavor text, its better placed in it's own section or, the attack very concisely summarized followed by anything else.
As stands, the effects read very elaborate for a y1 FEAR attack, visual or not. Not only does she suddenly get flames that 'fill' she sword, but they fill in ration to how strong her attack is, and they cover her arm, and are 'only decorative for now'. By having all this just for a y1 is very much running on elaborate and showy. I recommend toning it down to one visual effect- the flames are a theme and if you like the idea of them filling the blade then have them fill the blade to a certain point. As she gains years/xp, the blade gradually fills.
Think of everything from another player's perspective. If you're in a fight and just need X info, the more time you have to spend reading just to find the info the less you'll enjoy it. Summarize and limit. The more complex you make something, the more distracting it becomes.
Other-
Firstly, I can tell you've put a LOT of thought into this character, and while that's good, a lot that is written is flavor/distracting to actual points. While I nearly always say elaborate, there is a fine line between elaboration and being too elaborate. You've got so much information here that it's actually detrimental to me since points are being lost and reasons being lessened.
One big issue I notice however is the predetermined traits. Determining how other characters react to your own closes them off and makes reactions forced when the goal of a trait is more or open interpretation and flexibility. You can't predict how other character react to your own. Rather than 'On the first glance she
is cold and serious in' having it as 'On the first glance she
can seem cold and serious'
Avoid using 'always' and 'never'. Unless a trait is 100% that way no exceptions, then try to avoid wording it as such.
Also, she has almost no 'good' qualities. She's a 'b***h' and while that's fine... what makes her worth forming any relationship with? What makes a person want to be around her? What draws her empathy? Her emotions?
She also has apparently a lot of.. high skills. The quote box is rather filled with things with no apparent downside. For every skill or trait, there needs a balance. Characters are multifaceted, but by limiting yourself to only expressing this uber cool 'sexy, young, disciplined, refined, badass fighter, with infinite talent, clever, manipulative, ice cold, hidden, able to read ancient manuscripts' Etc etc. She has no drawbacks in her personality. It makes her seem flat and cliche, which runs against the detail you've very obviously put into her.
I would suggested narrowing your focus down into points
She is X, Y, Z
from there, expand how how each trait is both bane and boon, how each factor connects and builds.
NOTE:
Because you provide no info on her past- this is honestly a red flag as a GM. When a player purposely alludes to a shaky past yet provides no context to what the actual past is, it makes us a bit leery. Even if characters will not know this info, if it bears weight to the character and can possibly run counter to shop canon then please provide info! There is nothing wrong with having a hidden past ICly, but if that past isn't at least summarized to give context to both GMs and players, there is a risk that it might actually break shop canon or shop rules.
I hope this helps.