TTS worked with Sikka and was behind the deaths of Sargam and VP.
Saraswati came to TTS mansion and took Krishna home as she did'nt want her daughter living in the same house that VP's murderer lives in .
Saraswati had asked Krishna to dress and be the same as she was before marriage .
but now we get to see the symbolic side to it as Krishna will be studying again , she still wears sandoor on but never really wore mangal sutra even when she lived in TTS mansion