Originally posted by: bangtanARMY
I think I know what's the significance of Ab marrying Yu, it is to teach bhabhi lover the importance of marriage.
As a self-claimed Seer, I can already see the scene playing out:
(Ab & Yu at the mandap, the latter about to put sindoor in her maang and then comes Ar the bhabhi lover, grasping the wrist of Yu)
Ar: NAHIN, YEH SHAADI NAHIN HO SAKTA HAI!
MERI BIWI KA MAANG SIRF MERA! 
Ar to Ab: Maine tumhe tumhara maa ke samne tumhe sindoor aur mangalsutra dala tha - kaise tum isse Shaadi kar loge 
Meri patni, meri BIWI ho tum. Shaadi koi mazaak nahi
Chalo utho!
(And Ar the bhabhi lover takes his dealwali biwi away)
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