Whosoever you may be, O beautiful girl, we are fortunate in being able to see you. While playing with a ball, you have agitated the minds of all onlookers. Demons arrange many kinds of performances to see the glaring beauty of a beautiful woman. Here it is stated that they saw the girl playing with a ball. Sometimes the demoniac arrange for so-called sports, like tennis, with the opposite sex. The purpose of such sporting is to see the bodily construction of the beautiful girl and enjoy a subtle sex mentality. This demoniac sex mentality of material enjoyment is sometimes encouraged by so-called yogīs who encourage the public to enjoy sex life in different varieties and at the same time advertise that if one meditates on a certain manufactured mantra one can become God within six months. The public wants to be cheated, and Kṛṣṇa therefore creates such cheaters to misrepresent and delude. These so-called yogīs are actually enjoyers of the world garbed as yogīs. Bhagavad-gītā, however, recommends that if one wants to enjoy life, then it cannot be with these gross senses. A patient is advised by the experienced physician to refrain from ordinary enjoyment while in the diseased condition. A diseased person cannot enjoy anything; he has to restrain his enjoyment in order to get rid of the disease. Similarly, our material condition is a diseased condition. If one wants to enjoy real sense enjoyment, then one must get free of the entanglement of material existence. In spiritual life we can enjoy sense enjoyment which has no end. The difference between material and spiritual enjoyment is that material enjoyment is limited. Even if a man engages in material sex enjoyment, he cannot enjoy it for long. But when the sex enjoyment is given up, then one can enter spiritual life, which is unending. In the Bhāgavatam (5.5.1) it is stated that brahma-saukhya, spiritual happiness, is ananta, unending. Foolish creatures are enamored by the beauty of matter and think that the enjoyment it offers is real, but actually that is not real enjoyment.
(Srimad Bhagavatam---------3:20:35---------translation and purport).

So we should be very... Brahmacārī, there are so many restrictions. Even to see woman—"A beautiful woman is going, let me see"—that is also forbidden. That is also subtle sex enjoyment. Gross and subtle, there are so many subtle sex enjoyments—to think of woman, to see a beautiful woman going on the street, or to talk about woman, to read about woman. There are eight kinds of subtle sexual intercourse. So it is restricted. But in the Kali-yuga it is very difficult to follow all the rules and regulation. One is not trained up. Even up to ripe old age, one becomes attracted by beautiful women. Especially in the Western countries. I have seen in Paris, old man, seventy-five years old, eighty years old, they are going to the brothel. They are going to the night club. They are purchasing ticket to enter into the club-fifty dollars. Then they have to pay for the woman and wine and everything. In this way... So hṛd-roga-kāma, this hṛd-roga, hṛc-chaya, is a heart disease. It is very, very difficult to avoid unless one is fully Kṛṣṇa conscious.
(Lecture on Srimad Bhagavatam------Vrndavana, 1975).

Here our feelings of happiness is sex life. Sometimes we think, "Oh, how I was enjoying sex life with my wife, with my husband." That is also pleasure. They read so many novels because there is sex life. They feel very happy: "How this man is talking with this woman, woman is talking, this woman, and how they are enjoying." So that is subtle, subtle enjoyment. There are eight kinds of subtle sex life. If you see one beautiful woman and if you appreciate, "Oh, how nice the face is," that issubtle sex. If you read books, that is also subtle sex. If you endeavor how to approach that woman or man to find out the opportunity, that is subtle sex. There are eight kinds of subtle sexlife. So it is forbidden for a brahmacārī even to think of woman. That is brahmacārī. Even thinking of woman is subtle sex life. It is very, very difficult. But mām eva ye prapadyante māyām etāṁ taranti te [Bg. 7.14]. If you catch the lotus feet of Kṛṣṇa very tightly, these things will not disturb. That is said by Yamunacārya. Bhavati mukha-vikāraḥ. If you become pure devotee of Kṛṣṇa, then as soon as you think of sex, you'll spite. "Eh! Nonsense. What is this?" This is the result. That is the certificate, whether you have got that attitude—spite on it. Then you understand that you are increasing. Otherwise you are in the same hellish condition. You may show that you are becoming a devotee, very great devotee. So test yourself, how much you have advanced.
(Lecture on Srimad Bhagavatam------Vrndavana, 1975).

On the outskirts of that city were many beautiful trees and creepers encircling a nice lake. Also surrounding that lake were many groups of birds and bees that were always chanting and humming.
Since the body is a great city, there must be various arrangements such as lakes and gardens for sense enjoyment. Of the various parts of the body, those which incite sexual impulses are referred to here indirectly. Because the body has genitals, when the living entity attains the right age—be he man or woman—he becomes agitated by the sex impulse. As long as one remains a child, he is not agitated by seeing a beautiful woman. Although the sense organs are present, unless the age is ripe there is no sex impulse. The favorable conditions surrounding the sex impulse are compared here to a garden or a nice solitary park. When one sees the opposite sex, naturally the sex impulse increases. It is said that if a man in a solitary place does not become agitated upon seeing a woman, he is to be considered a brahmacārī. But this practice is almost impossible. The sex impulse is so strong that even by seeing, touching or talking, coming into contact with, or even thinking of the opposite sex—even in so many subtle ways—one becomes sexually impelled. Consequently, a brahmacārī or sannyāsī is prohibited to associate with women, especially in a secret place. The śāstras enjoin that one should not even talk to a woman in a secret place, even if she happens to be one's own daughter, sister or mother. The sex impulse is so strong that even if one is very learned, he becomes agitated in such circumstances. If this is the case, how can a young man in a nice park remain calm and quiet after seeing a beautiful young woman?

(Srimad Bhagavatam---------4:25:17---------translation and purport).