Even I was wondering a month back why Sai does this? I could only think of a girl I knew!! She had lost her mother at early age, she moved in with her nani nana and mama mami with her 2 siblings. 3 of them stayed with her mothers family. Her college time was full of chores and the same thing Sai does!! Early morning wake ups and late night sleeps, sadly, but 100% true was zillat arena as well! That Zillat arena was done by nonother than her nani. The girl and her sister were targeted on daily basis. They were made to work around the clock, nothing they did was ever enough. On top of it, they didn't let them eat as well. Kaku throwing food plate was one of her experiences too, another one was being thrown dishes at her when she was caught reading her course work in kitchen while making tea for the family. Even then they would love them. One of the biggest reason for them was they knew their father broke down after their mother's death and he was no longer able to be a normal father. They knew they had no one to call their own apart from each other. They had no place to go till they finish their education and start earning. Also, I saw they felt gratitude for small things, even though they didn't mention it in conversations. If they were asked to leave that toxic place they would only use one argument that its not so bad and they have roof over their head and grandparents and uncle and aunts. One big thing the girl mentioned once was at this house they don't have to worry about sexual abuse because people were waiting for them go get out of this place to prey on them!! I feel Sai has lot of these too and she is all alone, doesn't even have siblings for moral support!!
They felt not loved, but felt they had some security in return of torture. Both the sisters felt that their chastity was protected in that house, but out side they would have to loose it. To me it makes sense, but not sure how you would find this answer!!
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