Mark Crilley's Video: How to Draw a Big Eye Manga Girl
Mark Crilley's Video: How to draw a "realistic" Manga face
Mark Crilley's Video: How to draw a "realistic" female face
Mark Crilley's Video: How to draw a wolf video
Mark Crilley's Video: How to draw a kitten video
Mark Crilley's Video: How to draw a tiger
Mark Crilley's Video: How to draw a lion
Hopefully, you have enough video references here to create a line drawing that is a contour drawing or an outline of image for you zentangle.