Take their hands, for example, and study them.
His are soft, ink stained, barely calloused by anything heavier than pencil or tool.
His are hard and boney, scarred and calloused from gun grips and blade handles.
Or their eyes.
His liquid like, and so dark as to be black. They smoulder sometimes, and harden others but mostly the dance with laughter. They are warm.
His the colour of storm clouds, shades of grey that fracture and shift. They soften sometimes, and harden others, but mostly they are neutral, unreadable. They are not cold, but implacable.
We could juxtapose their domains.
His magic written in ink on flesh. Delicate hands make pricise works of art that represent, heal, strengthen, protect… He answers no prayers but will see you well cared for, for a price.
His magic is in the bullet and the knife if occassion must demand. His eye sees true, his breath steady and he vanishes quietly amongst the shadows. He is what answers when the sniper exhales and pulls the trigger – see my shot straight. He is what answers when the loved one prays come home safe.
Juxtapose these two, both small and slightly built. One short haired and the other long, one raven locked and the other silver though they are of age with each other.