▶ AUDIO
▶ VIDEO
▶ ACTION
▶ I REGULARLY MAKE NEW FRIENDS.
▷ 2. There is a bit of a dichotomy with Mitsuru in that she's arguably the most popular girl in school yet early on in the game has precious few people that she would actually call "friends". She's confident when talking and interacting with almost anybody but she's reluctant to actually let people in or let down her walls enough to become emotionally close to anyone. None of this is helped by the fact that her peers tend to find her intimidating. Her formality to the point of aloofness is demonstrated by the fact that she strictly observes the traditional rules of only referring to others within her peer group by their surnames, only switching to given names in exceptional circumstances when she's really gotten to know someone. Unlike her classmates who are much more willing to address each other on less a formal footing much more readily.
Of course things change as events progress in her canon and she grows closer to the other members of SEES (the Specialised Extracurricular Execution Squad - a group of teenagers fighting monster called Shadows under the guise of a school club), however she still retains that somewhat guarded element to a degree outside of the group.
▶ SEEING OTHER PEOPLE CRY MAKES ME WANT TO CRY TOO.
▷ 4. While Mitsuru can certainly be an empathetic person at times, she isn't someone who expresses extremes of emotions easily of her own accord, let alone because someone else is. She tends to want to be the level headed person in emotionally fraught situations and would prefer to be the anchor for others than let herself got caught up in the turmoil with them. Whenever one of her teammates in canon become upset, she's usually there to be that calming voice of reason or to just stand by them in support.
▶ I OFTEN MAKE A BACKUP PLAN FOR A BACKUP PLAN.
▷ 1. When it comes to strategy and planning, Mitsuru is often the one to take the lead, hence her leadership role within the Student Council, as well as in SEES. She also tends to veer towards overthinking quite often, wanting to analyse every possible scenario from every angle and plan accordingly.
▶ I USUALLY STAY CALM, EVEN WHEN UNDER A LOT OF PRESSURE.
▷ 2. She tends to be the person people look to in a crisis because she rarely loses her cool - there's seemingly a reason her Persona's element is ice. Even if she might be internally having a meltdown over a situation, she will always do her best not to let that show externally to others, even her close friends in some cases. However, there are exceptions. Mitsuru is the type to feel more at home leading her friends into battle against monsters than she is going on a date, she's likely to consider the latter more of a high pressure situation that the former and she definitely doesn't want you to see her flustered.
▶ I AM VERY SENTIMENTAL.
▷ 2. While she isn't a person who is devoid of feelings entirely, Mitsuru isn't someone who is usually prone to excess of sentimentality. She tends to try and keep her feelings and emotions under wraps, initially perceiving doing otherwise as some kind of weakness and she remains pretty undemonstrative the majority of the time even after a lot of character development. Being raised in a upper class family like hers means that she hasn't been raised to be all that revealing of her feelings. We see this in game when she and her father (who she loves dearly) see each other for the first time in a while and the way they greet each other is more like a pair of business associates than a father and daughter who do care deeply for one another.
▶ EVEN A SMALL MISTAKE CAN CAUSE ME TO DOUBT MY OVERALL ABILITIES AND KNOWLEDGE.
▷ 3. Mitsuru was born into the Kirijo family, they are powerful, rich and head a international mega corporation with scary amounts of influence over day to day life in the world of Persona 3. Mitsuru is the heir to all of that and as such is incredibly hard on herself. While a small mistake is rarely enough to dent her overall confidence in her abilities and knowledge, it will be enough to have her analyse what she could have done better in any given situation - mainly so she can do much better next time. She's a perfectionist and it shows. After a battle, she's usually the one of the group who spends time looking at their performance and what they could have done better.
▶ I AM MORE INCLINED TO FOLLOW MY HEAD THAN MY HEART.
▷ 4. As previously mentioned, Mitsuru is expected to have an arranged marriage, which she fully intends to see through despite the fact that the man she is expected to be with a) doesn't care about her and b) is a pretty vile human being. Her reasons for this are purely that she is doing what is advantageous for her family's company and to strengthen their position from a business point of view and that it doesn't matter what she might want from an emotional standpoint. She only sways from this path due to the protagonist's intervention and that takes some doing. Her words and actions are nearly always from a point of rationality and thought and rarely from emotions.
▶ I AM PRONE TO WORRYING THAT THINGS WILL TAKE A TURN FOR THE WORSE.
▷ 4. She does show concern for potential negative consequences, usually when one of her teammates/friends is on the verge of doing something foolhardy and she will remind them of their need for caution. However, she's not someone who spends a lot of time "worrying" in the traditional sense or over things that aren't actually important.
▶ I ENJOY WATCHING PEOPLE ARGUE.
▷ 5. If anything, Mitsuru tends to be the one who would intervene to stop an argument. She takes no pleasure in pointless conflicts that achieve nothing and when her teammates come into conflict with one another, as mentioned above, she is usually the voice of reason once again. As a founding member of SEES, along with Akihiko Sanada and Shinjiro Aragaki, the two boys are often prone to bickering and even fist fights on more than one occasion. While the relationship between the three of them isn't all that well fleshed out during the events of Persona 3 itself, other canon material (the drama CDs and further games) within the series does demonstrate that Mitsuru often ends up having to intervene and calm down their squabbling when she's present. It is established that they've all known each other for years, with Mitsuru usually being the mediator of the three.
▶ I TEND TO AVOID DRAWING ATTENTION TO MYSELF.
▷ 4. Being the center of attention is something that she's had to accept from an early age due to her family name and her position as heiress to the Kirijo Group. During the course of the game she's frequently the center of attention at various points, such as making a speech in front of the entire school and she seems perfectly comfortable with the situation. However, it is notable that during these instances she is maintaining a carefully curated persona, the perfect heiress and straight A student that she wants the world to see.
▶ I OFTEN DO THINGS AT THE LAST POSSIBLE MOMENT.
▷ 1. Absolutely not. She's a planner through and through and prefers to be prepared for almost any eventuality that may occur. As mentioned previously, she tends to be the one who is always reminding the other members of SEES when they've got exams coming up and expresses disapproval if they leave any studying they need to do until the last minute and don't start preparing well in advance. There is also hidden content within the game that occurs if you don't start fighting Shadows and venturing into Tartarus early enough, wherein she reminds you of your need to get started as soon as possible and to stop procrastinating and fulfil your duties as field leader.
▶ I FIND IT EASY TO EMPATHIZE WITH A PERSON WHOSE EXPERIENCES ARE VERY DIFFERENT FROM MINE.
▷ 3. Mitsuru can empathise with people who have different experiences but only to a certain extent. It has to be something she can relate to at least a little and/or tangentially. Early in the game, one of her teammates, Yukari Takeba is having extreme difficulties in summoning her Persona, in fact she's unable to. Mitsuru, who has been able to summon hers since she was a young child, seems to show little regard or empathy for the other girl's position. She tasks Yukari with getting their newest recruit to safety when Shadows attack the dormitory, expecting her to be able to do the necessary and summon her Persona if the situation calls for it, knowing full well that the other girl hasn't been able to do it. It doesn't occur to her to put herself in her position.
However, on the flip side of this, she does show empathy for another one of her teammates, Fuuka Yamagishi. Fuuka is a shy, awkward girl, not particularly popular and a target for bullies at their school - in distinct contrast to Mitsuru who is both popular and confident and whom most would be too afraid to bully. The bullying Fuuka experiences eventually leads to her being trapped in a life or death situation and she goes missing for several days. Her disappearance is hushed up by one of the teachers who claims that it is simply due to illness. When the truth is revealed and Fuuka is rescued by SEES, Mitsuru is furious and ensures that the aforementioned teacher is severely punished for the part he played in the situation. She can relate to Fuuka, as different as they are, because she too has been placed in a situation where people with power over her have forced her to do things she doesn't want to. This gives her the common ground she needs in order to be able to empathise with the other girl.
▶ I BECOME BORED OR LOSE INTEREST WHEN THE DISCUSSION GETS HIGHLY THEORETICAL.
▷ 4. As mentioned before, debating theories and planning are kind of her thing. She's been shown initiating discussions on theories on the methodology of different kinds of leadership in her down time when she absolutely has no need to talk about such things, when she's "off the clock" as it were. Yet she does it anyway and appears to enjoy it. She is definitely the type to enjoy a good old philosophical discussion over a cup of tea. If you manage to get close enough to her during the course of the game, she does reveal that she often spends time thinking about what it would be like if she were to run away from her duties as the Kirijo heiress, to take off on her motorcyle and never look back. This is all theoretical of course and she knows she would never do such a thing in reality.
▶ I RARELY FEEL INSECURE.
▷ 4. Generally speaking she's not someone who feels insecure often at all and she's an extremely confident individual, however she can veer towards being shy and nervous in certain social situations. For example, when she goes out for ramen for the first time her immediate response is: "Please tell me what the etiquette here is. Are there any customs I need to follow...?" because she's so concerned about acting improperly for that environment or saying and doing the wrong thing. A lot of this is tied up in her need to be perfect and being overly critical of herself.
▶ I AM STILL BOTHERED BY MISTAKES I MADE A LONG TIME AGO.
▷ 1. Not only is she bothered by mistakes she herself made, one of the most notable foundations for Mitsuru's character is that she feels it is her duty to atone for the role her family played in essentially bringing about the "big bad" of the game. While she states that her reason for fighting is ultimately to protect her father, it's clear that she feels responsible for events that have occurred and that she must deal with them accordingly - even if she was just a child at the time and played no part in it any of it. This is further evidenced by the fact that even beyond the timeline of Persona 3, she is still working to do that in her future.