A drawing I made in ballpoint pen with a green base layer (slide 2 for b/w filter), mixing two types of lines to keep the hair on another "layer" for better readability.
Green Lantern Ballpoint Pen Scribble Art Print – Cody James by Cody
Amazon.com : Camel Camlin 24 Shades Sketch Pens with Free Stencil -(Assorted)-Pack of 2 : Arts, Crafts & Sewing
Harry Styles Green Pen ORIGINAL Drawing - Etsy
Aibana-pen (Erasable ink pen for rough sketch on fablic) – Aikuma Japanese Dyes