"Why are you so self-conscious over that for?"

Question

I've met this phrase in a manga translation.

The context:
Let's suppose there are two characters - Bill (male) and Jane (female). An accidental kiss happened between them yesterday. Bill didn't consider it as something worth paying attention to, while Jane was the opposite.

On the next day, when Bill asked Jane about some important matter, she was still spacing out because of this kiss, so Bill said:

"Why are you so self-conscious over that for?"

I understand when a sentence ends with a preposition like "This is not the thing I can put up with.", but there I can't think of a verb that has this for.

My point is - I understand that this for gives some additional flavor to this sentence, but I don't understand the grammatical side of things.

Could anybody explain it, please?

Answer 1

As written the sentence is perhaps barely idiomatic, and certainly not elegant. As Colin fine mentions in his comment, the writer confuses "why" with "what for" -- but this is occasionally how native speakers talk, so I couldn't mark it as definitely wrong.

More idiomatic possibilities:

Why are you so self-conscious about that?

What are you (being) so self-conscious for?

However the use of "self-conscious" here is odd. It's probably a direct translation of the Japanese word, but a native speaker would be more likely to say

What are you feeling so self-conscious for?

Or, more naturally:

Why are you so upset about it?

or, more colloquially:

Why are you so worked up over it?

You also have to consider the cultural differences between the Japanese and most English-speaking countries, and what might be the stereotypical behavior exhibited in things like Japanese comic books that might not necessarily make sense to a non-Japanese person.