Slender lorises spend most of their life in trees, traveling along the tops of branches with slow and precise movements.

The name Loris is first reported Georges-Louis Leclerc, Comte de Buffon in 1765, representing the Dutch loeris meaning "clown".

[4] In India, slender lorises are known as devanga-pilli (దేవాంగ పిల్లి) or arawe-papa in Telugu, kaadu-paapa (ಕಾಡು ಪಾಪ) in Kannada, Kaada Naramani (ಕಾಡ ನರಮನಿ) in Tulu and wanur-manushiya in Marathi.

In Sri Lanka they are known as unahapuluwa (උනහපුළුවා) in Sinhala, in Tamil, spoken across southern India and Sri Lanka and in Malayalam, spoken mainly in the Indian state of Kerala, they are known as kutti thevangu (in Tamil தேவாங்கு, வா(வாக்கு) விலங்கு(ங்கு)) (kattu-papa, Kadapapa, or theivangu (meaning 'the slender-bodied one') and in Malayalam കുട്ടിതേവാങ്ക് or കുട്ടിസ്രാങ്ക്.

To maximize protein and nutrient uptake they consume every part of their prey, including the scales and bones.

In addition, slender lorises are illegally smuggled to supply a growing exotic pet trade.

[13] Along the western region of Tamil Nadu, there is a vigorous clampdown on illegal poaching of slender lorises.

[14] Furthermore, development of major cities in the regions the slender lorises inhabit, including Colombo, Kandy, Jaffna, Trincomalee, Bengaluru, Thiruvananthapuram, Chennai, and Nellore, has lead to destruction of its habitat; however, as shown in Bengaluru, urban populations of the gray slender loris can survive in urban areas provided there is enough tree and forest cover.