Was "defenestrated" simply a literal translation, or part of a bigger concept or joke?

Question

WorldEnd: What Are You Doing at the End of the World? Will You Save Us? (aka Shūmatsu Nani Shitemasu ka? Isogashii Desu ka? Sukutte Moratte Ii Desu ka? (終末なにしてますか? 忙しいですか? 救ってもらっていいですか?), commonly called SukaSuka) is a currently airing anime of Spring 2017. It should be obvious from the title that the author is very particular and non-traditional with their word usage. As strange as it sounds, the title of the series fits excellently. The English sub translation has flowed very well.

However something in episode 8 struck me as odd at time mark 14:00 (if watch, start 30 seconds earlier for context). Willem, the main character is speaking with Chtholly, who is in love with him. He is defending himself from light jealousy. When she counters an argument of his with an alternative case, he says with wit and resignation:

Defenestrated in two seconds flat.

I did not know what "defenstrated" meant (basically, in this context, he acknowledges she has completely dismissed his argument and admits defeat.) It is not often I need to look up a word while watching anime, and on top of that figure out how that word fits the situation.

What I wonder now is if the translator used "defenestrated" as simply a literal translation of a Japanese word, without any real thought. My suspicion is the opposite, that this is a contextual translation which would probably seem just as odd (and as oddly appropriate) in Japanese as it does in English. What kind of translation was it, and does it carry the Japanese intent well?

Update

HotelCalifornia (HC) further researched this question, and it turns out my original interpretation of "Defenestrated in two seconds flat." was incorrect. I had assumed the meaning to be [My argument was dismissed in two seconds flat.] As HC learned in the Japanese SE, a much better meaning uses a different subject and adds an object (both absent in the literal Japanese as well). So a translation that better fits conversation flow is:

I would have thrown Nygglatho out the window in two seconds.

(Nygglatho is the attractive female adult leader of the "warehouse", and Chtholly had just asked what Willem would have done if she had crept onto the couch where he was sleeping, instead of the teenage female who had actually done so.) So the primary meaning for defenestrated was the proper one, not the figurative meaning of dismiss.

Answer 1

After listening to the exchange a number of times, it sounds to me as if he is saying

「2[秒]{びょう}[以内]{いない}に[窓]{まど}から[捨]{す}ててるな。」

Ni byō inai ni mado kara suteteru na.

To break it down:

• Ni byō: two seconds
• mado kara suteteru: throwing out from/through a window

(the rest of the sentence is mostly structure, and immaterial to this answer)

My translation of the line would be something along the lines of:

[My argument] didn't last for two seconds before being thrown out [a window].

In other words, the translation (though the word choice may have been odd) was a literal translation, while also carrying some of the Japanese intent.

Update:

I asked about it on the Japanese SE, and have determined two things:

1. I misinterpreted the subject of the phrase- rather than his argument being dismissed, he is referring to what he would do "if it was Nygglatho" (namely, throwing her out the window). This applies to Crunchyroll's English translation as well.
2. The phrase 「窓から投げ捨てる」 (to abandon by throwing [something] out through a window) is a slangy phrase usually used to tell someone what they can do with an inferior product (akin to the English phrase "shove it up your ass." So, the Japanese phrase is figurative in a different way than the direct English translation.

An updated translation could be

[Nygglatho? I'd] throw her out the window in two seconds.

Answer 2

To "defenestrate" is the act of throwing somebody out the window. Maybe what he was saying was that an idea or an argument by him was shot down very quickly by the girl. I have not watched it yet, but from what you said, it may be that he is saying that anything he said was not cared for and simply "thrown out the window" very quickly. It is rather a literal translation but I think it might actually have been on purpose to show that his argument was ignored completely.