Shadow Knight

Sonic is the prince of a vast kingdom. Shadow is a knight who was first ordered to watch over Sonic when he was a young man, and later became the captain of the entire army.
Sonic and Shadow loved each other. Secretly escaping to the attic, they would hug and kiss while no one was watching. It was a wonderful time, when Shadow found the meaning of his life, and Sonic was happy.
But fate had other plans, and Sonic's parents—the King and Queen—decided to marry the prince off to Amy Rose, a princess from another, smaller kingdom, for political reasons.
Upon learning this, Sonic ran to the attic and wept there for a long time, though he had never allowed himself to cry before.
But his grief was interrupted by footsteps on the stairs. It was Shadow, who had no idea yet that their love was coming to such an end.