So what makes a character a "chaste" character?
There are certain implications and characteristics which make a character appear chaste. Some of those are down to general characteristics associated with a chaste character (shyness, not reacting to flirtatious behaviour, as well as diffiulty to accept intimacy). Some are down to cultural perception of certain roles (One example would be the famous "nun", or "sisterhood").
The plutocracy and "wild celebrations" of Antiva, combined with accents from countries such as Spain and Brazil, certainly don't convey that image to me.
Not until after the relationship starts at least.
The very beginning of something that could be considered an intimate relationship proves that there was flirting from both sides. You can't start a relationship without knowing that the opposite party is heavily interested. My Inquisitor did not force a relationship on Josephine, she readily accepted on her own terms. That means she flirted back, both verbal and non-verbal. The idea that an intimate relationship could start without any form of flirtatious communication from one side is ridiculous.
So people who don't flirt but are in relationships are forced into them according to you?
You seriously mean to imply that there is an intimate relationship out there that did not previously involve flirting, be it verbal or non-verbal? There is a reason for characters moving just the way they do. There's also a reason for making two dozen recordings of a single important line just to get the sound "just right". It's called "body language" and "emotional suggestion". A character doesn't need to openly say: "I think you are handsome!" to actually flirt.
The idea that a romantic relationship could start without both parties previously conveying interest or attraction is ridiculous. This "conveying of interest", be it verbal or non-verbal, that's usually called "flirting".
I'm curious though. You've been arguing with potential cases and "exceptions" for some time now. Can you provide actual evidence of such a relationship existing beyond "I'm in one! Believe me!"?
Solas is such an example, since he was written to have it be ambiguous and yet is the most popular romance in DAI.
That's a false argument based on your own implication of why the romance was good. I just googled your statement, but I couldn't find any evidence about Solas being "by far the most appreciated one."
I will take it at face value now and accept that he was, but that doesn't have to be down to being ambiguous. When I read about why Solas was such a good romance option, the general opinion is usually because of his general characteristics. Compliments. Behaviour. Ideas. Story. All of this does in no way imply that the ambiguous nature made it the desired romance for most. That is something you might be interpreting into the results based on you liking the ambiguous nature of it, but it doesn't have to be the reason Solas is appreciated in the way he is.
Can you provide evidence too? A survey or article which produces unrefutable evidence that Solas was appreciated because he was overly ambigious in terms of sex?