Curse is a status in Final Fantasy VIII. A cursed character is unable to use their Limit Break. However, if the command was selected before the status was inflicted, they will still use it. The effect lasts approximately 21.3 seconds. Curse is opposed to Aura and the two statuses are unable to coexist on the same target.
In the Ultimecia Castle, the player's commands are sealed until unlocked by defeating the castle's bosses. Limit Break is one of the sealed mechanics, and during it, the player cannot use Limit Breaks no matter if they have Curse or not.