Chastity is a virtue which depends on the virtue of modesty. Everyone should get in the habit of avoiding the giving and receiving of temptations against the ninth and sixth commandments.
I recall that in a tour book for Israel there is a note on female decorum in Middle-Eastern society, for example, females should not go about unaccompanied. There are similar admonitions regarding modest attire.
It is interesting to note the norms on this in Saint Augustine's Rule for Sisters. In the present #MeToo world we do well to consider how "unwanted advances" may often be intentionally and unintentionally invited. What is more, Sodom necessarily requires a specific code of modesty. Remember that only one family was saved from Sodom, the family that left, and only those who left without looking back! "And [Lot's] wife looking behind her, was turned into a statue of salt." Genesis 19:26
Chapter X.
Let there be nothing remarkable in your habit and do not seek to please by your dress, but by the dispositions of your heart. Let not your veils be so thin as to show the head-dress beneath; nor shall your hair be uncovered so that it may be neither negligently dishevelled, nor artfully put up in a knot.
When you go abroad, walk together; when you come to your destination remain together. Whether you walk, stand still, sit, or make any movement, let nothing be done which may stir any one to concupiscence, but let all be conformable to holiness, that is, to the holiness of your vocation.
Chapter XI.
If you cast your eyes on any man, nevertheless fasten them on none. You are not indeed forbidden to see men when you go abroad; but to desire them, or to wish them to desire you, is a criminal fault; for it is not only by the touch, but by the mind and the eyes, that a woman is desired and desires. And do not say that your intention is modest if your eyes be immodest; for an immodest eye is the messenger of an immodest heart, and though the tongue keep silence, when hearts wantonly entertain each other with mutual glances, and concupiscence moves them to take pleasure in sinful desires, even if the body remain chaste, chastity none the less perishes in the heart. And she who fastens her eyes on a man, and likes him to return her look, must not imagine that her so doing will be unobserved. She is certainly seen and by those she little thinks on. But suppose that no one notice her conduct, how will she hide herself from Him Who looks on from on high from Whom nothing can be hid? Can we, I ask, think that He sees not our actions, because he sees them with patience proportioned to His wisdom and knowledge? Him, therefore, let the devout woman fear to displease, that she may not cherish the evil wish to please any man. Let her remember that God sees all, that she may not desire any man to cast sinful looks upon her; for the fear of Him is enjoined on us,, and for this very reason where it is written; He is an abomination to the Lord (Pr 11, 20), who fixes his eye on evil.Chapter XII.
When, therefore, you are together in the Church or elsewhere in the presence of men, take a mutual care to preserve one another's chastity, for by this means God, Who dwells in you, will preserve you from yourselves. And should you perceive that any one of you is making free with her eyes in the way I speak of, admonish here at once, that those beginnings may not go any farther, but be then and there corrected. And if, after your admonition, you see her repeat the same, or perhaps another day, then she who shall have perceived ti, whoever she be, shall make her known as one already wounded, that she may be cured. But before this be done, the same fault ought to be brought to the notice of one or two others, that she may be convicted by the testimony of two or three (cf. Mt 18, 16) and corrected with suitable severity. And think not that by detecting this evil you are showing her any ill will; for , on the contrary, the fault would be were you by your silence to permit your sisters to perish, when by accusing them, you might lead to their amendment. For if your sister had a sore in her body which she wished to conceal for fear of an incision, would it not be cruelty to keep silence and kindness to make it known? How much more then ought you to manifest a spiritual ulcer, that it may not fester more dangerously at the heart?
Rules of the Institute of St. Augustine, for the Sisters