Paint Tool SAI

Sketch: 30min-1hr
Outline: 30-40min.
Colour: 1-2hrs

(c) 4LS, Weee, RAITA etc.

Unmarked text version: [link]
sketch: [link]

EDIT:
Busy with personal projects, school projects, upcoming lessons, classes etc. Final year of college, so amount of submissions will decrease.
Updates may (or may not) be on a monthly basis.