A knight on a white horse moves slowly across a landscape, a cup held out before him. Unlike the other knights, his pace is measured. His armour is mostly ceremonial. He is on a quest, but it is a quest of the heart.
Classical readings call this the romantic, and the deeper frame is following feeling deliberately. The Knight of Cups moves where his cup points him — toward connection, toward art, toward whatever quiet thing is calling. He is the courtier in the suit of relationships, capable of beauty and also capable of being out over his skis when feeling is mistaken for fact.
Reversed, the same idealism becomes mood. The pursuit of a fantasy rather than a real person or situation. Disappointment when the rendered version of the beloved does not match the actual person. The shadow is the suitor who is in love with the project of being in love rather than with the one in front of them.
When the Knight of Cups appears, the reading is often acknowledging a generous-hearted move you are making or one that is coming toward you. The work is making sure the cup is being held out to what is, not only to what was imagined.
One card, one motion.