Yakshas & Yakshinis: The treasure keepers, attendants of Kuvera, the keepers of wealth, semi-divine beings sometimes considered as ghosts and spirits of demoniac possession.

Kuvera: 'The treasurer of the demigods' - There is mention of Kuvera in several cantos of the Bhâgavata Purâna. See for example: 1:9-3, 2:7-33, 4:11-24, 4:15-14, 5:10-17, 9:2-32, 10:10, 10:34-25, 11:16-16.

Kâr(t)tikeya (Guha, Skanda): The younger son of Lord S'iva and His consort Pârvatî; the presiding deity of warfare (riding a peacock) [SB: 10:51-16] 

Kinnaras: the ones of superpower said to be capable of changing their form at will. [see S.B.:  7.8: 55)

Durgâ: Goddess; Heartens the struggle for material interests of mahâmâyâ ('the great illusion' - the bewildering potency of the material world). The impersonation of the material energy and the spouse of Lord S'iva. She is elegant and feminine as Pârvatî or Uma, but as Durgâ she is cruel and as Kâlî she is bloodthirsty (see Kâlî).  (see also Uma)

Usha or Ushas (= 'shine' or 'east'): Goddess of daybreak on her cart, pulled by seven cows, from them it is said that they represent the seven days of the week. 

Râvana abducting Sîtâ:  A mighty demon called 'ten-head', who wanted to build a staircase to heaven and pave the streets with gold, but by Krishna in His Râma- incarnation was killed after he had abducted Sîtâ [see: Ramakatha Rasavahini, chapter 3a&3b The Wily Villain] and also S'rîmad Bhâgavatam:  9-10, 9-15, 10-40, 11-4, 11-12 &  (2-7, 4-1, 5-19, 5-24, 7-1, 7-10).

Hanumân: Monkey-god who led Lord Râma's vanâras (ape-like) in the battle against the demon Râvana. He is carried in the banner of Arjuna as a sign of victory. [see: Ramakatha Rasavahini, chapter 5b: Success in the Search] (See also the prayer of Hanumân SB: 5-19, and the SB. Râma-chapters: 9: 10 & 11).

Kâlî: Goddess unto whom meat-eaters perform their sacrifices. (see also Durgâ)

[Kali-yuga: (iron age) era of quarrel and strife that commenced after Krishna's departure 5000 years ago, eighteenth of February 3102 B.C, and is characterized by the four human weaknesses that form the opposite of the four religious virtues, the four legs of the bull of dharma (sauca, tapah, dayâ, satya): free sex, gambling, eating of meat and intoxication as opposed to purity, sobriety, compassion and truthfulness: the regulative principles. (see also SB: 5.6: 10, 5-9, (Bhadrâ Kâlî), 1.16 & 17).

- The faithful ones [of spiritual progress] knowing of the value, praise the age of Kali pointing out it's essence that by [mere] congregational chanting as good as all one's goals are attained (11.5: 36).

- To this S'rî Caitanya Mahâprabhu qouted a verse from the Brahma-vaivarta Purâna:

asvamedham gavâlambham
sannyâsam pala-paitrkam
devarena sutotpattim
kalau panca vivarjayet

"In this age of Kali, five acts are forbidden: the offering of a horse in sacrifice, the offering of a cow in sacrifice, the acceptance of the order of sannyâsa, the offering of oblations of flesh to the forefathers, and a man's begetting children in his brother's wife."]
[Further texts in SB about Kali-yuga: 1-1, 1-3, 4-8, 9-12, 9-22, 10-20, 11-5 & 11-7]