/3/ - 3DCG

Hi, I'm not sure if this is the right thread for this, but i'm trying to set up a rig in blender and have a question.
The selected bone in pic related is my foot IK bone, I want the actual foot bone (the bone that slopes down to the toe bone) to copy the rotation from this footIK bone, but then offset that rotation so that when the foot IK bone is parallel to the horizontal axis like it is in the pic, the foot bone will be at the same angle it is at in the pic.
Basically I want to just be able to control the feet with only the movement and rotation of the foot IK bone, but playing around with copy rotation constraints it seems I can only set it to the exact rotation of the foot Ik bone, and not add an offset.