Tsundere is a term often used in animé fandom, of which, for the avoidance of doubt, I am not a constituent, which is a portmanteau of the Japanese terms tsuntsun, meaning "turning away in contempt," and deredere, which, I'm told, means something like "all lovey dovey."
So a tsundere is a person, usually a woman, who alternates between these two extremes. One day they'll be coming on to you all lovestruck like you're sex on legs and you make her insides go all squishy and squirmy. Then the next she'll hate your guts and think you're pathetic and contemptible. But the next day she'll be all, "hey, I'm sorry, I didn't mean it like that, etc. etc." But the day after that she's painted "Flopsy" and "Mopsy" atop her saucepans. Well, maybe not in that quick succession, but someone who is tsundere can go from one extreme to the other at the drop of a hat.
Now I'm not here to plough through the entire corpus of animé and manga to give you examples of tsundere folks in action. TVTropes does that far better than I ever could, and in any event, the only animé I have deliberately watched has been the metallicious Bastard!!. Which, to be fair, has its share of tsundere folks in it. Yoko for one. And Thunder Empress Arshes Nei. But that's another node. Rather, I'm going to tell you about actual, real life, tsundere folks, and why they're not cute or hot or interesting, but are, in fact, !!!!A PAIN IN THE ARSE!!!!
You see, and this is no joke, having a tsundere attracted to you really sucks. I would refer you to the following case study.
When I was seventeen, I encountered a very tasty and very bright (this is important for me, I can't stand stupid people) girl who we'll call Lana because it's almost her name. Lana was, for want of a better term, thoroughly gorgeous. She was just under six feet (I have a thing for women who can look me in the eye), had lovely curlyish hair (I cannot stand the idea that it has to be all straightened out, let's frizz a little!), a pair of hips that wouldn't quit, legs up to here, and a bustline that constantly threatened to escape. I make no apologies for this last criterion, it is a fact of life that Lana had awesome bewbage and anyhow, I WAS SEVENTEEN and was eager to break the habit of a lifetime. She seemed nice. Really nice. And I wanted to get to know her better, hopefully with a view to getting to know her biblically, if I'm honest. However, as a seventeen year old rather nerdish headbanger, this wasn't on the cards. It took me some time before I decided it was worth asking her out (or, in retrospect, I procrastinated.) And she accepted. Most profusely.
Being seventeen and a slightly nerdish headbanger, I was quite thrilled at this. Whoo! She really wanted me, at least judging by the fact that she sent me a text message a few days beforehand explaining how she was drifting off to sleep thinking of me and doing other things while so thinking, and looking forward to Saturday. Yep, that's right. She admitted to splittin' the kitten over me.
And then come The Big Date, was all cold and lifeless. Honestly, it was like hanging out with a corpse. And afterwards turned quite ugly (metaphorically, that is) and said how I was just trying to take advantage of her or just interested in getting her into bed, and told me that such was "not bloody likely."
(Before you ask, no, I never told her she had awesome bewbage, nor did I make any other crass comments towards her.)
And then a few days later I ran into her unexpectedly and she was all blushing and stumbly and bumbly and thought she'd been "exceedingly harsh" (true) to me about this and wanted to apologise because she thought I was nice and sweet and "would be excellent boyfriend material." (Did I mention that to go out with me in the first place, she ditched her previous beau like a shot?) Anyhow. My ego swelled. Woo yay! Victory will be mine! Hazelnut, douze points!
So, on a whim, I invite her to go and see the Rocky Horror Show which was touring in my town at that time. She says it's sweet of me to offer but she's not interested.
And a bit after that she's exceedingly harsh to me yet again.
A bit later, I run into her at a party and she's coming on really strong to me and so on and so forth. Afterwards I get another fruity text message or suchlike as I have already related. When next I speak to her on the internets she's all frosty and going on about how maybe she "misjudged her feelings" and then tells me how she thinks I'm a total and irredeemable cunt.
I decide I've had enough at this point and tell her as much. I don't call her a tsundere though because that word was as yet unknown to me. I do, however, call her a "fucking mentalist hellbitch" which gets her well bent out of shape. Understandably. But it was the truth.
A few weeks pass. I run into her later on and she's really, really, coming on to me and I think, aha, I'll give it a go. I ask her out. She accepts. It goes really well. I mean, really, REALLY, well. She's all over me in the back of the cinema, well, sort of. Afterwards she goes all shy and blushing and I suspect I'm about two steps away from some filthy squeezing. However, considering her track record of being, well, tsundere, I don't quite go for the brass ring, if that makes sense. Which is entirely excusable; how was I to know that if I had she wouldn't have gone all, "I hate you! I hate you!" again. So I hold off somewhat.
Turns out she WANTED me to go for it and try to, erm, get fresh, to use an Americanism, with her. Because I didn't I'm accused of having no "gumption" (she was ever fond of that word), and being insensitive and so on and so forth. I try to explain that I had no way of knowing what she was wanting me to do considering she was always blowing hot and cold in this manner and so forth, which falls on predictably deaf ears and she goes into yet another snit. This one even features a blog post from her devoted to slagging me off! Jesus Titty Fucking Christ.
I would go on but I'd just be repeating myself. By the time the saga ends she's irretrievably fucked up one of my closest friendships, caused me to be an object of ridicule among people who I didn't care too much about anyhow but had to be around on a daily basis, and I still never got to sleep with her. I call that a total rout, don't you, friends and neighbours?
In fact, Lana thoroughly fucked my view of relationships and women for years afterwards. I remember that throughout the whole of my first year and a half of university I was so subconsciously convinced that any woman attracted to me (and in retrospect there were quite a lot, now I think about it and some of the stuff they'd say or do!) was a tsundere who was just out to arse me around and blow hot and cold all over my face. Even when a very nice pharmacology student who we'll call Catriona would often invite me to her room while she was in her PJs and half-cut and wanting to talk about personal things would set alarm bells ringing. I'd be thinking, "Does she actually want me or am I just being taken for a ride here - and not the sort of ride that I want to be taken for?" And because of this I would inevitably seem uninterested and lose their interest. Gnagh.
When it finally dawned on me that only a psychotic minority of women were tsunderes, I was too bitter and cynical to be attractive to any women.
And that's why tsundere is not fun, attractive, cute, or adorable. It's a pain in the arse and it's really, really, really, annoying and in no way an attractive trait in anyone, ever.
(Node 25 of 30 IRON NODES. Like you care, you bastard. Except you're not a bastard. Sorry. But I still think... yeah, you heard. And so forth ad infinitum.)