She stood at the sink, unaware that he had intercepted the postcard from her secret lover. Well, this certainly explained the nightly headache, the avoidance, the general lack of respect.
He set to work on perfecting a convincing alibi, as he planned the dark sequence of events to follow. Hurting her would be new to him, but it would be easy enough to get her on the roof; a simple pretence of removing the holiday lights should do. She'd never hear his tread behind her.
"It's a shame, really," he thought to himself. "I'd have preferred to keep this one."