It's sort of weird with me. In summary (for those who don't want to read everything), I think it's almost entirely my quietness that would put most people off - would put guys off, and also would keep acquaintances/friendships at bay. In a purely romantic context, the other thing that applies is that I simply am not interested, romantically, in most guys. I have pretty high standards in terms of who I want in my life in a deep/meaningful/real way, and with everyone else I'll deliberately keep things pretty walled off and I'll talk about myself if asked, but I really won't elaborate a whole lot - mostly pleasantries and my just asking them questions. I am almost positive this is read [correctly] by most that I am not interested - hence they don't pursue.
When I DO like someone though? I think it's fairly obvious. In the end, I think I come across very feminine, and I know that I can't stop my body language from showing if I like someone - inflections of the voice, eye twinkles, the way I smile, whatever. Now I'm not one who's overly demonstrative, so I won't touch the other person much (or at all), but it's more subtle. I still think guys would pick up on it though. As one silly example, I have the unfortunate affliction of *blushing* pretty readily. It can be very embarrassing as I can't control it. But my boyfriend likes to point out when I do blush. lol. I bring that up because it's something that would be obvious if I were with someone, and like them, and at certain moments I'd probably blush....
I don't think I'm seductive or scary. I'm not... effusive enough to be seductive, I don't think. I'm too contained. I'm not scary either, although like I said in the beginning, I DO put up noticeable walls that keep others at bay. Walls aside, the common theme that I get all the time is that I am 'sweet'. I don't exactly understand it (honestly) - that this is a universal view - but most acquaintances I meet end up citing this. Especially of late, everyone references me as 'sweetie' or 'sweet pea' (when saying bye to me), or this older gentleman friend of my boyfriend told my boyfriend recently that I was a 'real quality girl' and if anyone messed with me, they were messing with him. I hear this stuff and I'm like... really? Holy crap, I hardly say a thing, and I treat people respectfully... is this such a rare thing and as such I'm universally Sweet and guys end up wanting to protect me? I actually find it kinda sweet. lol!!! haha. It's like I exude this feminine/cute/innocent/sweet vibe (again - definitely not seductive, le sigh) -- which will obviously be alluring to certain sorts but totally boring to others. Not that that really matters... I mean I like who I like, and I'm not out in the market for some 'protector' or any such thing (I'm very self-sufficient and independent), nor is any of this an act where I'm putting on airs or even consciously trying to 'be sweet' or whatever. I'm just being my usual quiet self, being nice to people.
Edit: I've also mused too over the impact of ones own genetics/physique, and corresponding cultural associations with said physique. So with myself, given my build, my voice pitch, my facial features, and the like, there's no way in hell I'm going to be able to carry off the 'seductive' vibe - as culturally viewed. Which is why I'm always 'cute' and 'sweet'. Whereas I have an INFJ friend who is over 6 ft tall, dark hair, more exotic looking, more curvaceous, and she'd totally pull of the seductive vibe rather than the 'cutesy' vibe. The two of us next to each other, interacting with the same guy, would end up impacting the guy in different ways, simply by virtue of our differing looks. I'm not saying this is the only thing behind such things as whether a person is viewed as 'seductive' or 'scary' or whatnot, but it certainly plays a part.