Juan Francisco Casas is an absolutely amazing artist who works with only a ballpoint pen. The artist creates stunningly realistic portraits with the use of a pen, some of which can be seen in the gallery above.

Spanish artist Juan Francisco Casas seems to capture sensual moments in his art as women are drawn in provocative poses.

Implications - It's really incredible that Juan Francisco Casas is able to create such lifelike portraits with only a pen. Normally when I doodle with a pen I just produce aimless drawings, so I'm especially impressed with his work. Just imagine having every mistake be fatal to the drawing as a whole. That's a lot of pressure!