Section 154 CrPC does not mandate that only victim can lodge the FIR. Any person can register the FIR if he knows that a cognisable offence has been committed. In Prakash Singh vs State of Punjab, the Supreme Court held that police officer could not make an inquiry about genuineness of FIR.
The Supreme Court held that sexual intercourse by taking consent on the false promise of marriage amounts to the offence of rape. As far as section 90 & 375 IPC is concerned, if the consent was taken by the misconception of fact, i.e. the false promise of marriage, it is not a valid consent and accused shall be punished for the offence of rape