Illustrate a portrait of a person using a muted gray monochromatic palette. The subject should have soft, gentle features, and the entire image should be rendered in various shades of gray. Use a standard lens with a moderate aperture to capture the fine details of the portrait. The lighting should be soft and diffused, creating gentle highlights and shadows that add depth to the face. In the background, add a simple, textured backdrop in a slightly different shade of gray to enhance the cohesive look. Apply a light vignette effect to draw attention to the face and a touch of soft focus to create a calming, dreamy aesthetic.