"There is the vipralambha-sakhya, the higher fraternal worship of the Lord especially enjoyed by the cowherd boys. Although there is friendship between Krsna and the cowherd boys, this friendship is different from the aisvarya friendship between Krsna and Arjuna. When Arjuna saw the visva-rupa, the gigantic universal form of the Lord, he was afraid for having treated Krsna as an ordinary friend; therefore he begged Krsna's pardon. However, the cowherd boys who are friends of Krsna in Vrndavana sometimes ride on the shoulders of Krsna. They treat Krsna equally, just as they treat one another, and they are never afraid of Him, nor do they ever beg His pardon. Thus the raga-marga, or bhagavata-marga, friendship exists on a higher platform with Krsna, namely the platform of vipralambha friendship. Paternal friendship, paternal service and conjugal service are visible in the Vrndavana raga-marga relationships."
Srimad-Bhagavatam 4:24:45-46
The names of the twelve most important cowherd boys are Sridama, Sudama, Vasudama, Subala, Mahabala, Subahu, Mahabahu, Stokakrsna, Dama, Arjuna, Lavanga, and Kusumasava.
Of the twelve cowherd boys, Sridama is considered to be the chief. Sridama carries a flute made of a bamboo stick with sixteen knots. His complexion is fair and ruddy, and he is like a splendid red lotus flower. Sridama used to put on a yellow colored dress. He would carry a buffalo horn and his turban was of a reddish, copper color. His bodily complexion was blackish and around his neck there was a nice garland.
Sridama would always challenge Krishna in joking friendship. He used to address Krishna: "Oh, you are so cruel that you left us alone on the bank of Yamuna and we were all mad from not seeing You here. If You now want to pacify us, You must embrace each one of us with Your arms. But believe me, my dear friend, a moments absence from You creates great havoc, not only for us but for the cows also. Everything becomes disarranged and we become mad after You."
He is expert at singing and dancing, is fond of flower garlands and sandal paste, and is expert at writing love letters. He displays the ecstatic symptoms of perspiring and standing erect of the bodies hairs. Krsna would sometimes perform mock fighting along with the cowherd boys. When Krsna blew His horn in this mock fighting, Sridama, who was on the opposing side, felt his bodily hairs stand up.
"Lord Krsna's friends in Vrndavana, headed by Sridama, have pure fraternal affection for Lord Krsna and have no idea of His opulences. Although they fight with Him and climb upon His shoulders, they worship His lotus feet in a spirit of servitude. Some of the friends of Sri Krsna, the Supreme Personality of Godhead, massaged His feet, and others whose sinful reactions had been destroyed fanned Him with hand-held fans."
Caitanya-caritamrta, Adi lila 6:62-64
"Learned scholars have divided Krsna's age into three periods: the age up through five years is called kaumara, the age from the sixth through the tenth year is called pauganda, and the age from the eleventh through fifteenth year is called kaisora. While Krsna is spending His days as a cowherd boy, He is in the kaumara and pauganda ages. ....The kaumara age is just suitable for reciprocating the love of a child with mother Yasoda. In the Tenth Canto, Thirteenth Chapter, verse 11, of Srimad-Bhagavatam, Sukadeva Gosvami tells King Pariksit, "My dear King, although Lord Krsna is the supreme enjoyer and the beneficiary of all kinds of sacrificial ceremonies, He still used to eat with His cowherd boyfriends. This is because at that time He accepted the pastimes of an ordinary boy, keeping His flute under His arm and His bugle on the right side in His belt, along with His cane. In His left hand He would hold a lump of rice paste with yogurt, and in His fingers would be pilu, the king of fruits. When He would thus sit among His friends, it would appear that He was the whorl of a lotus flower and that the friends surrounding Him were petals. As they thus enjoyed joking among themselves, the denizens of heaven would become struck with wonder and would only stare at the scene."
Nectar of Devotion, Chapter 41
"Subala's body is described as follows. His complexion is just like molten gold. He is very, very dear to Krsna. He always has a garland around his neck, and he wears yellow clothing. His eyes are just like lotus flower petals, and he is so intelligent that by his talking and his moral instructions all the other friends take the highest pleasure. Let us all offer our respectful obeisances unto Krsna's friend Subala! The degree of intimacy shared by Krsna and Subala can be understood by the fact that the talks between them were so confidential that no one else could understand what they were saying.
....When Krsna and Subala were embracing one another, Srimati Radharani became a little envious, and hiding Her hot temperament She said, "My dear Subala, you are very fortunate because even in the presence of superiors you and Krsna have no hesitation in putting your arms on each other's shoulders. I think it must be admitted that in your previous lives you have succeeded in many kinds of austerities." The idea is that although Radharani was accustomed to putting Her arms on Krsna's shoulders, it was not possible for Her to do such a thing in the presence of Her superiors, whereas Subala could do so freely. Radharani therefore praised his good fortune."
Nectar of Devotion, Chapter 41
Bhaktivedanta Book Trust. HDG A.C. Bhaktivedanta Swami Srila Prabhupada.