Hi Max, you are right this time it is different effect in compare to the scribbles, somehow looking at this drawing the straight lines give an impression of calm atmosphere and a touch of fragility softness to the character. Maybe like a flowing water. Especially when it goes over to hair texture. Nicely showed the building up the intensity of values with places the lines closer and another way around giving some space between gives an impressive of highlight.It is an important skill to have a good eye to be able all that tricks in order to build up good natural portrait.