Abstract tattoo subjects provide a chance to design the entire tattoo around the natural contours of the body part. In this sleeve design, the overall tattoo follows a basic S-curve pattern while parts of it address specific muscle features on the arm. Notice how a horn shape above the elbow makes use of the bulge and indentation at the top of the brachioradalis, while major features curve down the front of the bicep, angle up the back of the tricep and frame off the deltoid.