Oh, 'mystery artist' (though I suspect many of us will indeed guess who you are, as your beautiful style is so distinctive), what a sublime picture! The rosy hues are just a contrast to the reality you draw: two men who have lived their lives, and their faces show it.
What I adore is how, even though they are facing in opposite directions, even though their expressions are contrasts in emotional personality, even though there were so many reasons why they shouldn't have been together, and shouldn't have stayed together, their eyes are still drawn towards each other.
You can see the good humor in Harry's expression, and the fierce loyalty in Severus.' I especially like the contrast in their complexions, and how Severus seems to still shelter or protect Harry with his body, even after all of the years.