THE "MAGNET" AND THE "PIN"
I think this PIN has a great symbolism in the story
Let me explain:
Yash is the Pin that can always attracts with the Magnet
Aarti is the Magnet.
Prashanth is the Plastic in comic sense,but in sensible sense he is the Silver churn that can't attract to a Mgnet.

I said this bcoz ,when a magnet is surrounded by a Pin and Silver Churn,Magnet get attracted to the Pin only...[that's my Yashu]
Magnets attract iron pin[my yash is an iron man]due to the influence of their magnetic field upon the pin.
Also remember the words of Baba ,Baba said to Yash about this magnetic field of love of yash and Aarti,Isn't it??
So any external fields[kaki,bua,dubey]tries to separate my AArya ,it doesn't work .Bcoz Aarti is the Magnet and Yash is her IRON Pin.So under theirlove magnetic field,no one get an entry.No one can separate my Aarya,they are well bonded and attracted to each other ,forever'
The plastic/silver churn prashant dreams won't work!!!
Bcoz a silver churn can't stay in the magnetic field,it is out of the field'..