Floor-to-ceiling windows frame her silhouette in “ballbusting hammer” as she touches herself in broad daylight. The risk of being seen only heightens arousal. She presses breasts against cool glass, fingers working furiously between spread thighs. City noise fades under her moans. Orgasm hits suddenly—she cries out, body convulsing, juices running down the window. “ballbusting hammer” is fearless, exhibitionist erotic art.