As Cloak was a very difficult character for me to achieve, I couldn't find much that resembles him. There are a couple of pieces of artwork that helped me tie his character together, granting the idea for the white strip of hair and the angle of his horns, but for the most part, I wanted him to have a rough look to him after a long life of living the way he has. 

This first artwork granted me the idea for the white strip of hair (which does have a meaning that'll be revealed later in the series), as well as the angle of his horns. I hadn't quite decided if I wanted them to curl, but finding this artwork helped me decide. 

Credit: https://www.deviantart.com/lorandesore/art/Adaar-606625288

This next one also resembles him closely, mainly the face shape and harder features.

Credit: https://www.deviantart.com/lorandesore/art/Qunari-619914053

This one closely resembles the scar at the corner of his mouth. 

Credit: Unfortunately, I couldn't find the credit for this but their watermark is in the corner.