Only wife or girlfriend AFAIK. Assuming both have reached the age of consent.

If wrong, please correct citing relevant sections / cases. Thank you.

According to IPC section"198. Prosecution for offences against marriage.—(1) No court shall take cognizance of an offence punishable under Chapter XX of the Indian Penal Code (45 of 1860), except upon a complaint made by some person aggrieved by the offence: 

Mr ramachary is absolutely right.Aggrieved person can file complaint against the man.

Dear Friend,

You are a married person and without getting divorce you can not make any s*xual relation with any girl as it will amount to the Offence of Adultery.

Adultery is a crime against the state as well as a cruelty against the living wife. Here the sufferer is the wife but in the given situation the wife herself is not residing with you so in this case the any person who is not an aggrieved party can  not lodge the complaint of the Adultery.as per Sec 198 of CrPC. as it is an offence against marriage.

Here I would like to point out if the girl in live-in relationship is a minor her parents can complain against you of kidnapping and rape.

As per the precaution is concerned, I can not suggest you any ,as the crime is a crime no doubt.

I agree with the Adv Ramachary and disagree with our young Adv Ms Simi Salooja.

I differ from all the above replies made in the concern of the asked query.

The above gentlemen have moved slightly away from the topic "Aultery" which is the prime source of cause of action.

Its clearly mentioned here that girl is major and unmarried. So, charges of adultery can't be prosecuted on the author who is alleged in the livin relationship with that girl.

Reasoning:

1. Adultery charges can be filled by only the aggrieved husband of adulterous wife u/s 497 ipc on other man who has established s*xual relationship with her wife.

2. In this case girl is not having any husband rather than a boy friend who is author himself.

3.Author's wife can only charge her husband here author in civil procedure only i.e she can get divorce from him on the ground of adultery, which will cause authors delight as he himself wants to divorce her wife. So, here if wife approaches for divorce on such ground then author will get relief indeed.

4. Now, on the part of rape and kidnapping:

A. No kidnapping charges will be levied here because under ipc kidnapping charges are made only for minors and hence for majors abduction charges are levied. But, here the mens rea of abduction doesnt follow because the girl herself inclined to live with her boyfriend. So, in such case neither rape will prevail nor abduction as both the charges are made by the intention of good faith and a valid consent from the major girl.

Therefore, no person can punish him for such activities alleging the case in hand.

Ps: In india a begger can also file cases on any person whom he thinks to harass but the moot point is that he will get nothing out of blues.

So, any case filled on pertaining to adultery will be not maintainable in any way.

But, yes author's wife can file 498a and dva and maintenance cases at any time if she wish to harass her husband.

ESIS

Just for my clarifications :

a) What is the definition of an " aggrieved" person as used in IPC 198 ? And according to that who are such persons in this specific case ?

b) What is the offense being made out ?  As said above "adultery" does not hold u/s 497 since here the girl is not married to begin with. So which section holds and what offense is made out ?

c) As for live in relations per se, the Hon'ble SC has no objections to it, except that the woman will get the status of marriage only if the male is not already married. See :

https://www.hindustantimes.com/india-news/live-in-relationship-neither-a-crime-nor-a-sin-sc/article1-1156842.aspx

However, that does not seem to be the issue here since the girl in question seems to know that the male is married.

So, what is the offense and who are the aggrieved  ? Any sections / case laws ?

why do u want to dig ur own grave ?

get divorce first & then get involved in other womem