Is it permissible to kill a woman who threatens to commit Zina and causes problems?

The abomination of zina (fornication/adultery) is among the worst sins and acts of disobedience. Allah Almighty has forbidden it and blocked all paths leading to it, such as seclusion with a non-mahram (definition), immodest display (tabarruj), and unlawful gazes. He has also commanded lowering the gaze.

A Muslim must create a barrier between himself and zina. Threatening a woman with problems does not justify falling into zina. One can get rid of her through other means, or by reporting her to the authorities.

It is not permissible to even consider killing her, under any circumstances. Killing a soul is one of the gravest sins. Allah Almighty says: "And whoever kills a believer intentionally, his recompense is Hell to abide therein, and Allah has cursed him and prepared for him a great punishment." [An-Nisa:93].

And Allah Almighty says: "And those who do not invoke with Allah another deity or kill the soul which Allah has forbidden them to kill, except by right, and do not commit unlawful sexual intercourse. And whoever does that will meet a penalty. The punishment will be doubled for him on the Day of Resurrection, and he will abide therein in humiliation. Except for those who repent, believe and do righteous deeds; for them Allah will change their evil deeds into good ones. And Allah is Oft-Forgiving, Most Merciful." [Al-Furqan:68-70].

A Muslim should turn to Allah and frequently supplicate to be rid of problems and destructive evils, just as Yusuf (Joseph) (peace be upon him) did: "He said, 'My Lord, prison is more to my liking than that to which they invite me. And if You do not avert from me their plan, I might incline toward them and be among the ignorant.' So his Lord responded to him and averted from him their plan. Indeed, He is the All-Hearing, the All-Knowing." [Yusuf:33-34].