Words I'm writing: Opening Lines

Is it just me? I suppose it is. I occasionally find myself writing books in my head. I never get beyond a few opening lines. Things like this:

Arnold, the neighbors' son, was an odd child. So odd, in fact, that many otherwise rational people occasionally entertained the notion that he might be of another world. In summer, he'd sit on the sidewalk for hours frying ants with a magnifying glass. One by one, they'd crackle faintly and curl up. I can hear you protesting—"I did that as a child!" 

But Arnold was different. Sometimes he would name the dead ants and take them home. He kept their corpses in a box. Sometimes he would pull the legs off one ant and feed its tiny limbs to another. He once showed me an ant carrying a leg, looking--as Arnold, himself, astutely pointed out--like the builder across the street who just then happened to be walking by, carrying a long 2x4 over his shoulder. Sometimes Arnold would eat the fried remains of an ant or two. 

As he got older, Arnold focused hot sunlight more often on things made of paper that burned in an entertaining way (I used to keep a bucket of water on my porch, just in case). As a teenager, Arnold was fond of killing stray cats and talking to the sky. Later in life, Arnold found a way to combine some of these talents: He killed his wife, dismembered her, and burned down his house, having consumed part of his spouse before the fire. The newspaper reports were unsure about his intent. Had he meant to roast her? Thankfully, Arnold had moved away by then.

Where to go from there? Nowhere really.