Indotyphlops porrectus
Range
Bangladesh, India, northern Myanmar, Pakistan and Sri Lanka (the source does not name Nepal)
Size
Up to about 28.5cm total length, about 0.5cm across
The slender worm snake, Indotyphlops porrectus, is a harmless blind snake of the family Typhlopidae, first described by Stoliczka in 1871. It is slender, up to about 28.5cm long and about 0.5cm across, with 18 rows of scales, brown or blackish above and paler below, with a whitish snout, chin and anal region. It lays eggs (Wikipedia, general species account).
The source places it in Bangladesh, India, northern Myanmar, Pakistan and Sri Lanka and does not name Nepal, so its Nepal status should be checked. It gives no habitat, diet or behaviour detail (Wikipedia, general species account).