Mystery Blue: A mysterious color that invites adventure. The barrel and cap have a harmonious silhouette with flowing curves, while a clip inspired by a raindrop adds a touch of elegance. Its transparent barrel lets you admire the ink even more. The crown features blue parts that evoke the sea, the icon of the 'Custom NS,' and expresses the wish that 'just as a river flows into the sea, the heart that cherishes someone will continue to connect without interruption'.