Meaning of Term:
‘Tsundere’ describes a character (usually female) who runs 'hot and cold', constantly changing between being a strict, confrontational and uncaring person (tsuntsun: "aloof" or "cranky" in Japanese) and an affectionate and soft-hearted person (deredere: "lovestruck" in Japanese).

Personality:
There are two main types of ‘Tsundere’, depending on their personality:

Type “Tsun”: These ‘Tsundere’s are “tsuntsun” set as their default “exterior”, making them seem mean. This is the usually personality given to Tomboys or ‘bad’ boys in Anime/Manga. It takes something very special to trigger their hidden “deredere” side. The intensity of their crankiness can range from “Always angry at practically almost anything that I don’t agree to” to “This is stupid, I ain’t doing it”. When they are angered or embarrassed, they usually become vulgar (by shouting insults to the other person) or sometimes violent (by hitting the person with their hands, legs or with a “trademark” weapon of choice). However, when they help out someone that they are not close to, they would probably say something like "Don't get me wrong, I'm not doing this for you" and usually have their entire face covered with ferocious blushing, making them appear vulnerable in contrast to their usual strong-willed exterior.

Type “Dere”: These ‘Tsundere’s have “deredere” as their default “exterior”. This is the usually personality for soft spoken people that seem nice but have a mysterious hidden background in Anime/Manga. They are kind and soft-hearted, but just happen to have a secret violent side too. Usually, their temper is almost always triggered by someone else, usually by their love interest or by an idiot which serves as a comedic relief. As they have absolutely no clue on how to handle feelings of love and attraction, they are therefore sweet to everyone except the person they are interested in. Unwanted suitors might also trigger their violent side. Very often, the male love interest (referring to female “deredere”s) will be very frustrated as everybody else keeps telling him how sweet the ‘Tsundere’ is and wonders how it could possibly be the same girl.

Types of Pairings (need not be romantic ones):
In Mangas and Animes, ‘Tsundere’s are usually paired up with the patient type of people, since a normal person would be pissed off by the former’s cold attitude.
A more common pairing would be with the seemingly-stupid and stubborn type, as sparks (more from anger than romance) are more likely to fly, contributing greatly to the ‘Comedy’ sector.
On the other hand, there is also the masochist type, but they are extremely rare and used only for comedy relief.

What makes them attractive:
A Tsundere's attractiveness can come from either side: On one hand, she is an independent, strong-willed person, determined to do everything well. On the other, she has major “turn-on” points such as awkwardness with relationships (particularly, romance) or have tomboyish tendencies (refer to female ‘Tsundere’s), which she perceives as "weakness". Furthermore, they rarely just sit back, do nothing and act the ‘damsel in distress’ as that will make them lose their appeal. For Type “Tsun”, it's assumed that the person acts fierce to hide their good intentions or as a wall for preventing their weakness to be shown when dealing with romantic relationships. For Type “Dere”, her hidden “tsuntsun” side shows that they are not just some nice guy.

Subcategories:
‘Kuudere’ – Rather than having a violent side, ‘Kuudere’s have a stoic, cold personality with a hidden “deredere” side. The range of intensity for their “Kuu” side can be from an emotionless robotic-like isolator to just a quiet, soft spoken person.
‘Yandere’ (mostly females) – Under normal circumstances, a ‘Yandere’ would only show his/her “deredere” side. However, mess with their love life (e.g. break up, discovery of an affair, insulting their love interest heavily) and they will go on a rampage, where some can go as far as murder (?). More or less a loose nut-case when a love relationship goes wrong.

Labels: Anime and Manga Corner, Chapter 11