Left Hand Slot
The Left Hand Slot refers to one of the 19 Equipment Slots on the Paperdoll. Items that solely occupy the Left Hand Slot are Shields, candles and lanterns, etc. While a Two-Handed Weapon "occupies" both of the individual Hand slots, most only are represented on the Paperdoll as being in the Right Hand Slot. The Swords of Prosperity are one of the few Two-Handed Weapons that acutally appear in both hands of the Paperdoll and the game window avatar.
Exceptions
One exception to the Two-Handed Weapon rule applies to characters with Grandmaster status or better in the skill of Ninjitsu. Such Ninjas can use both the Fukiya (blowgun) and Shuriken (throwing stars) while equipped with a Two-Handed Weapon.
Another exception exists for Archers. Bows with the Balanced Item Property behave as if they are One-Handed Weapons. When so equipped, a character can perform any action that requires a free hand, such as drinking a Potion or throwing a Shuriken.