Ah, this is the topic that needs to be studied before books can be validated. The word seems to be Thritheeya Prakrithi (addressed in detail in the “From Compilations” section below).

From Shruthi

In that same night Mitra implants seed in Varuna, and when it (the moon) wanes, then it is produced from that seed. Now as to why that oblation of curds (payasyâ) to Mitra and Varuna is here exactly analogous (to the Sânnâyya offered at new moon)

Satapatha Brahmana (2.4.4.19) (from sacred-texts.com)

But this one is likely a case of Devatha Tattva being used.

From Smrithi

From Purana

It is given punishments in Garuda Puraana, and it was also used in the movie Anniyan.

Garuda Puraana

todo

From Dharma Shaasthra

Should take bath:

मैथुनं तु समासेव्य पुंसि योषिति वा द्विजः ।
गोयानेऽप्सु दिवा चैव सवासाः स्नानमाचरेत् ॥ १७४ ॥

maithunaṃ tu samāsevya puṃsi yoṣiti vā dvijaḥ |
goyāne’psu divā caiva savāsāḥ snānamācaret || 174 ||

If a twice-born man commits an unnatural offence with a male, or has intercourse with a female, in an ox-cart, or in water, or during the day, — he should take a bath along with his clothes. — (174)

Manu Smriti, Chapter 11, Verse 174 (from Manu Smrithi with the commentary of Medhatithi from Sanskrit Wisdom Library)

NOTE

The right translation is “if a Dvija commits Maithunam with a male or female” - it is translated by splitting them into “commits an unnatural offence with a male, or has intercours with a female”

Loss of Caste (Jaathi):

ब्राह्मणस्य रुजः कृत्वा घ्रातिरघ्रेयमद्ययोः ।
जैह्म्यं च मैथुनं पुंसि जातिभ्रंशकरं स्मृतम् ॥ ६७ ॥

brāhmaṇasya rujaḥ kṛtvā ghrātiraghreyamadyayoḥ |
jaihmyaṃ ca maithunaṃ puṃsi jātibhraṃśakaraṃ smṛtam || 67 ||

Causing pain to a Brāhmaṇa (by a blow), — smelling at things that should not be smelt, or at wine, — cheating — and sexual intercourse with a man, — all this is declared to lead to loss of caste (Gatibhramsa). — (67)

Manu Smriti, Chapter 11, Verse 67 (from Manu Smrithi with the commentary of Medhatithi from Sanskrit Wisdom Library)

Expiation:

By discharging semen into inhuman females except a cow, into a woman in [her] menses, into others that have no female organs (i.e., a man or a eunuch), or into water one should perform the penance of Santapanam.

(Atri Smriti, Chapter 1, Verse 268)

About the case of cow, the context in the preceding verse was written (it’s just that the penance is different):

Prajapatya is laid down for holding sexual intercourse with a beast, or with a harlot. By holding intercourse with a cow, one should perform a Chandrayana spoken of by Manu.

(Atri Smriti, Chapter 1, Verse 267)

From Dharma Soothra

Depositing semen other than in the vagina or doings so outside her season:

One who does not have sex with his wife during her season, and one who has sex with her outside her season, as also one who deposits his semen in a place other than the vagina ––they all incur the same guilt.

Baudhaayana Dharma Soothra 3.7.2

A man who ejaculates his semen in any place other than the vagina becomes equal to a thief, equal to a murderer of a Brahmin.

Apasthambha Dharma Soothra 1.19.15

From Compilations

Pro-LGBTQIA Gaudiya Vaishnava Sect

Answer from Hinduism Stack Exchange:

From https://hinduism.stackexchange.com/a/30418/40901:

Amara Das Wilhelm (of GALVA108.org) describes the various kinds of homosexual males and females and also the causes of human sexuality and gender in ancient Hindu/Vedic society in his book “Tritiya-Prakriti: People of the Third Sex: Understanding Homosexuality, Transgender Identity, and Intersex Conditions Through Hinduism.”:

Homosexual men:

The Five Types of Kliba [Homosexual men]

In a chapter of the Sushruta Samhita (3.2) discussing the conception of progeny, five types of kliba are listed and described as follows:

  1. Asekya—he is aroused only by swallowing a man’s semen.

  2. Saugandhika—he is aroused only by smelling the genitals of others.

  3. Kumbhika—he takes the passive role in anal sex.

  4. Irshyaka—he is aroused only by the jealous feelings of seeing others in the act of sexual union.

  5. Shandha—he has the qualities and behavior of a woman.

The Sushruta Samhita is an ancient Vedic medical text put into writing sometime around 600 B.C. All five types of kliba are described as inborn, due to an equal “seed” conception caused by various conditions of the parents. The Sushruta Samhita distinguishes the shandha from the other four in that the latter are said to possess semen and male characteristics whereas the shandha is completely devoid of these. It also mentions that the first four types of kliba achieve erections through drinking the semen of other men (3.2.44-45) and describes a type of female shandha with the qualities of a man (3.2.43).

Homosexual women:

The Ten Types of Nastriya [Homosexual women, which is only the first two, the rest (besides 3) are mainly impotent and not necessarily homosexual]

Women who are impotent with men are mentioned less frequently in Vedic literature. Nevertheless, at least ten different types of nastriya or third-gender women can be found in various Sanskrit texts and are listed below.

  1. Svairini—she engages in lovemaking with other women.

  2. Kamini—she engages in lovemaking with both men and women. [“Kami” is the masculine i.e bisexual male]

  3. Stripumsa—she is masculine in behavior and form. [Not necessarily homosexual]

  4. Shandhi—she is averse to men and has no menstruation or breasts.

  5. Narishandha—her womanhood is completely destroyed.

  6. Varta—her female “seed” is afflicted in utero.

  7. Sucivaktra or Sucimukhi—she has an extremely small, undeveloped vagina.

  8. Vandhya—her menstruation is absent or suppressed.

  9. Moghapuspa—her attempts to unite with the man are fruitless.

  10. Putraghni—she has repeated miscarriages.

The svairini is described in the Kama Sutra (2.8); the kamini in the Bhagavata Purana (5.24.16); the stripumsa in the Mahabharata and various astrological texts; the shandhi, sucivaktra, vandhya and putraghni in the Sushruta Samhita (6.38); the shandhi, narishandha, varta, sucimukhi and putraghni in the Caraka Samhita (4.2; 4.4; 6.30), and the moghapuspa in various Sanskrit lexicons. The first three types are physically capable of bearing children whereas the remaining seven are infertile.

The causes of human sexuality and gender:

The Ten Causes of Gender

Both the Sushruta and Caraka Samhitas provide elaborate descriptions regarding how and why living entities take birth as male, female or third gender. Such descriptions can be summarized into the ten contributing factors listed below. In many cases, several or even most of these factors will be involved to some degree.

  1. Samskara—previous life impressions.

  2. Kama—desire.

  3. Sukarma—good karma.

  4. Vikarma—bad karma.

  5. Sukra-bala—strength of “seed.”

  6. Mithuna-vidhi—method of copulation.

  7. Paurusha—the personal efforts of the parents.

  8. Dosha—affliction.

  9. Prakriti—nature.

  10. Daiva—divine ordinance.

  11. Samskara—previous life impressions. According to Vedic teachings, the living entity is eternal and experiences innumerable lifetimes until achieving final emancipation. Thus, every newborn person comes with a complete package of previous life impressions, desires and activities known as samskaras. Based on these, the living entity takes birth as male, female or third gender.

  12. Kama—desire. Every living being has kama or innumerable desires as part of the previous life impressions or samskaras mentioned above. When the living entity desires to experience a lifetime as male, female or third gender, such a lifetime comes to pass.

  13. Sukarma—good karma. When the living entity takes birth as male, female or third gender according to desire, such a birth is said to be the result of previous good deeds or sukarma. A birth due to sukarma is evident when the person is happy with the awarded birth and resides in a setting where he or she is treated kindly. Such a person is furthermore endowed with auspicious qualities such as beauty, good health, strength, wealth, talent, intelligence, good parentage, righteousness, renunciation, religiosity, and so on.

  14. Vikarma—bad karma. When the living entity is forced to take birth as male, female or third gender against all desire, such a birth is said to be the result of previous misdeeds or vikarma. A birth due to vikarma is evident when the person is unhappy with the awarded birth and resides in a setting where he or she is treated harshly. Such a person is furthermore endowed with inauspicious qualities such as ugliness, ill health, weakness, poverty, lack of talent, foolishness, bad parentage, unrighteousness, excessive attachment, irreligiosity, and so on.

  15. Sukra-bala—strength of “seed.” According to the quantity and the quality of the parents’ “seed” at the time of conception, a child is conceived as male, female or third sex. When the father’s sukra or male sexual fluids predominate, a male is produced and when the mother’s sonita or female sexual fluids predominate, the child will be female. If both are equal, the offspring will be of the third sex. Such equal “seed” conceptions are further distinguished as follows: When the “seed” is exactly equal and afflicted, the child will be sterile or have both male and female physical characteristics; when the “seed” is mostly equal but slightly more in terms of the male or female, a third-gender boy or girl will be born respectively, and when the “seed” is mostly equal due to the profuse quantity and strength of both parents, a bisexual child is born. Thus, according to the bala or strength of the parents’ sukra and sonita, various types of male, female and third-gender offspring are produced.

  16. Mithuna-vidhi—method of copulation. According to Vedic science, the mithuna-vidhi or method of copulation can also determine a child’s gender by affecting the parents’ “seed” and attracting specific types of living entities to the womb. When upasriptaka or normal copulation is employed, the child will be either male or female but if citrarata or exceptional copulation is engaged in, a third-gender child will likely be the result. Such exceptional methods of copulation are further distinguished as follows: When the parents assume the purushayita or “woman on top” position, the offspring will be a male or female shandha who behaves like the opposite sex; when the wife assumes a complicated position during intercourse and the husband’s semen is weak, the child born will be a vakri with a deformed male organ; when the wife performs oral sex on her husband prior to intercourse and a son is conceived, that boy will be a mukhebhaga who performs oral sex on men, and if the husband performs oral sex on his wife prior to intercourse and a daughter is conceived, that girl will be a svairini who makes love to women. Thus, according to the parents’ mithuna-vidhi or method of copulation, various types of male, female and third-gender offspring are produced.

  17. Paurusha—the personal efforts of the parents. Parents generally desire heterosexual offspring—especially sons—and Vedic texts offer many helpful practices to assist them in this regard. The parents should keep good sexual health, take invigorating tonics, refrain from overindulgence, assume the upasriptaka or “man on top” position during intercourse, follow proper timing, observe prescribed rituals, consult astrologers, propitiate the gods and so on. At the time of conception, the consciousness of the parents should be peaceful and pure; they must have passion but not excessive lust, anger or detrimental feelings such as jealousy. In this way, the parents should apply personal effort or paurusha to conceive the offspring they desire.

  18. Dosha—affliction. Due to previous misdeeds and despite the best efforts of the parents, various afflictions or doshas can arise that result in the birth of sterile or malformed offspring. The word dosha refers to afflictions caused by some imbalance or aggravation of the three bodily substances known as vata, pitta and kapha (also called doshas). When afflictions occur in the sex organs, reproductive fluids, hormones, chromosomes or genes of either the parents or embryo of any sex, offspring are consequently born sterile or sexually malformed to various degrees.

  19. Prakriti—nature. When all of the above considerations are taken together they result in the aggregate factor known as prakriti or nature. The workings of material nature are subtle and mysterious yet grossly powerful. According to the stringent laws of prakriti, all living entities are forcibly born among the three genders in a series of countless lifetimes.

  20. Daiva—divine ordinance. The ultimate factor in regard to cause of gender is daiva or divine ordinance. Indeed, the laws of nature work according to God’s will and cannot be overruled. It is therefore daiva or divine ordinance that ultimately determines which of the three genders a living entity assumes. The various supernatural causes such as being cursed or blessed by a demigod or saintly person are also included within this category.

From the site itself:

https://galva108.org/f/tritiya-prakriti-people-of-the-third-sex (Continued in the PDF attached at the end)

Other

One Site:

http://history-of-hinduism.blogspot.in/p/homosexuality-and-hinduism.html

Thoughts

  1. Ardha-Nari-Eeshvar exists
  2. Ayyappa was born from Shiva and Vishnu (Mohini)