Who can we talk about when using 「そのスジの人」?

Question

The sentence is taken from Volume No. 5 of「 波よ聞いてくれ！」

The radio-host Minare is interviewing the spokeswoman of an underground cult. When she introduces her as a member of a cult the spokeswoman claims that she is working for a public-service corporation. After discussing this matter a bit Minare says the following:

「そのスジの人にはたまらない感じの線のほそーいハーフの美人なんですけども」

What I was wondering about is the 「そのスジの人」 .

There are several definitions and posts I found about it, however they somewhat disagree when it comes to the nuance/implication of this phrase:

• goo.ne.jp entry for 其の筋

• Yahoo! Japan

These definitions here seem to understand the expression as rather neutral, while the definition of 「筋者」, which popped up when I was searching for the meaning of the expression in question as well, clearly states that it is more or less only used when speaking about criminals. (zokugo-dict.com entry)

From the context of the Manga it is pretty obvious that mentioned spokeswoman is associated with criminals (and Minare knows that).

So, what exactly are the nuances of this expression? Is it a neutral expression used to somewhat hide details about a certain person or is it strictly used for people associated with criminal activity?

Answer 1

A dictionary definition of そのすじ is just in a particular area, circle. Thus そのすじのひと means people in a certain circle. As such it can mean any kind of people, even police (well, maybe not too different from criminals).

Without any contexts, however, そのスジ（筋）のひと tends to mean, like 筋者, people in a criminal circle (or more specifically yakuza, Japanese mafia).

That said, the particular line from the manga does not refer to any criminals. It literally says the girl is a type of half Caucasian whom certain people would like very much. (certain people = そのすじのひと). Now the obvious question is, what kind of people are those certain people? The answer is, those people who like half Caucasians like her (the girl in front of Minare).

As for たまらない, Consider a simpler sentence AはBが好きな人にはたまらない. This means *for those who like B, A is something that those people would be especially fond of, where B is usually a category A is a part of.

Example: このプリンはスイーツ好きにはたまらない Those people who like sweets will like this pudding very much.

Now to the line of your question: it means she is a particularly beautiful girl those certain people will especially be fond of. In other words, she has many features that make half Caucasians attractive.

A verbose translation: For those people who like half Caucasians (in general), she is a thin, beautiful type whom those people would especially like.

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Of several meanings of たまらない, the usage here is 4.程度がはなはなだしい.

A dictionary definition of 線が細い is only about (inner) character being sensitive or timid. But I think in practice it also implies physically thin - no sumo wrestler would be called 線が細い.

I put thin above for simplicity, but note that it surely is implying she is timid-looking.