It turned Marsha on when Gary killed roaches. It made her feel womanly. She had killed many herself, but derived an intense pleasure from watching Gary. She made a loud sound for his benefit when she saw one in her kitchen. It was fat and slow moving, probably dying from poison.
Gary looked around before moving to a basket of magazines in the living room. He rolled up a copy of Good Housekeeping and gripped it in his fist. Marsha liked that he would kill for her. She thought he was graceful. She found herself thinking about cavemen bringing down a mastodon.
Gary stalked the roach as it skittered across the tiles. He brought the magazine down, two hard thwaps, and the roach didn't splatter much. He scooped up the carcass, carried it to the bathroom, and flushed it. He put the magazine back in the basket, brown goo and a leg or two clinging to its cover. Marsha made him wash his hands, first.
What We Were Doing and Where We Were Going