Rat torned my RC book

I have a lancer 2nd hand. Few days back, a rat entered into the car and wrecked havoc everywhere,It even ate my RC book. Now how to get a new RC?

You can apply for duplicate RC in the RTO where the car is registered. You may need to produce the torned RC book though, if you mention the true reason for duplicate RC in your application. And AFAIK it wont cost you much. However, to get it done faster and have less pain on your head, you may want to contact any RTO agent to get this done. It would attract more cost though.