Part 2, because it didn't really fit into the main story but we couldn't leave it out entirely.
It pained Moist to see him like this. He rarely saw Billy anymore, the true Billy. Only on these few outings was he allowed a glimpse at his old friend. Awake and moving he was Dr. Horrible, confident and cold in the blood red lab coat and black lensed goggles that frightened away any glances fast enough that you could not see how thin the body beneath the fabric was becoming. Billy was only given the chance to float back to the surface when Dr. Horrible was asleep, and Dr. Horrible never slept, or ate, and barely drank. Billy really didn't come round very often. And when he did it was almost too painful to watch. While the doctor's thick lab coat and goggles hid his failing body, Billy's sweatshirt and thin pants did nothing to hide the skeletal figure, the dark bruises below his eyes. Dr. Horrible's hands were steady, immortal in their strength. Billy's shook in exhaustion and malnourishment. Snake Bite smirked once in passing and told him the fallows beneath the doc's eyes made his image more evil, sinister even. Moist pursed his lips and said nothing in return; he thought they were just his broken heart bleeding through his skin. The Evil League of Evil had found themselves the perfect soldier in Dr. Horrible: loyal, intelligent, quiet, and unable to feel pain. Only Moist ever saw Billy, curled unconscious on a fading grave, the listing unpolished headstone his only support. He'd brush away the tear tracks on his bony cheeks; gather the shaking, frozen limbs in his arms; lay on the grave Billy's gift; and carry him home. There he'd lay him on the bed gently, prying his jacket from clenched fingers so he could fetch more blankets. Half a bowl of soup would make its slow way into the blonde, never staying down for long. Moist would wait by his friend's side till morning, when Dr. Horrible would wake and stalk back to his lab. Moist would put away the blankets, make the bed, and wait.