Replicate "scan" lines in freestyle

I am observing the documentation page for the freestyle SVG exporter, and would like to know how to reproduce the effect demonstrated in the header image, shown below. I am specifically interested in the effect demonstrated on the Suzanne model, not necessarily the background.
images

I am frankly lost as to where to even begin, considering the fact that the model’s edges do not follow this consistent pattern, and thus I cannot use edge-marking.

The objective would be to create lines which trace around a model, as above, regardless of actually following any object’s edges or loops.

I’m fairly new to freestyle, and so
any help would be appreciated,
thanks.

Edit: sorry didn’t get that it need to be done in freestyle…

That would be possible, but only after aligning all transforms of the rotated head (selected one).