It was written within the context of the author being outed as a professor due to political pressure.
Contextually, some Argentinian political history and the author’s background are required, but as a standalone story, it’s a wonderful bit of supernatural horror.
I took an interest in this post and story, which I read, and found that while I appreciate the sentiment, there’s actually a lot of misinformation in the post itself.
Casa Tomada*
Brother and sister*
https://en.wikipedia.org/wiki/Casa_Tomada
Cortázar was not living abroad in 1946 when this was written. He wasn’t in France until 1951. In 1946, he worked at a university as a professor of French literature in Mendoza, Argentina, and was being outed by political pressure - this is more specifically what the story is probably about.