Criminal Fir done with false accusation

I am basically from bihar, and currently doing job in delhi. I am a tenant in delhi with rent agreement as proof of residence, and employed in a company. My relative's daughter (who is my sister in relation) has filed a criminal complaint i.e. FIR against me in ladies police station in their residing district of bihar. The accusations are false. 6 months ago I have given an informatory petition in SDO court of that district that they will do this in future, and as expected, they did. At that time, i.e. 6 months back while filling the petition, i had given a legal notice from my lawyer's end to them asking that they have done wrong to me, and I want to book a case against them, as in reality they had done wrong with me. They didn't replied that notice, and also I due to family pressure left the issue. Now, they had done a FIR on me and that to from ladies side. How safe I am ? Can I book my case which I was supposed to do 6 months back against them now? Also, can I book that in a court in delhi, as I do job in delhi? Also, please tell in which court in Delhi? Please inform.