Then quickly, for such a short, portly, elderly person, she disappeared. (Para. 7)
Meaning: Although she was short, over-weight and old, the woman disappeared all of a sudden.
for: prep. despite
For all his faults, we like him still. 盡管他有錯誤，我們還是喜歡他。
For all your explanations, I understand no better than before. 盡管你作了解釋，我還是不明白。
Please notice that "for" in this sense is usually followed by the word "all".
disappear: vi. go out of sight
The sun disappeared behind the clouds. 太陽躲進了云層里。
The man disappeared the same day the crime was committed; no one could find him.發生犯罪的那一天，那人消失了，沒有人能找到他。
The money disappeared from the bank; no one knew who took it. 那筆錢從銀行里消失了，沒有人知道是誰拿的。