Please they are really dil ke acche, but Sai is the vamp who spoiled Devi's life by bringing in Pulkit.
See their concern for Devi, esp Pakhi didi.
Sai wants to take revenge on Virat for her father's death and thats why she agreed to marry Virat. Usha Maushi was her pawn and Sai put her plan into action thru her.
Perfect explanation of Sankalekha’s imaginary world
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