Eric grinned when he saw the shudder travel through Bastian's body, and a shiver went up his own spine both from seeing Vala's reaction to watching him and from the pleasure that his touch elicited.
"The skin behind your knees is very sensitive too," Eric continued, lifting up one of his legs so that he could demonstrate by running his fingers over the specified spot. Another shiver ran up his spine at the light touch. "I don't think I'd realized that before."