My neighbor is definitely a serial killer

Emma Carter had been without her medication for eleven days when she first noticed the man across the hall dragging a large black suitcase down the apartment stairs at two in the morning. The building was quiet except for the awful scraping sound each step made against the concrete. He didn't struggle with the weight. Didn't curse. Didn't stop to rest. He just kept descending slowly, one floor at a time, his face hidden beneath the flickering hallway light. Emma stood behind her peephole in an oversized shirt, fingers pressed so tightly against the door that her nails bent white. When he finally reached the bottom floor, he paused for a moment and looked back upstairs directly toward her apartment. Then the lights went out.