The cursed seal is classified as a Kinjutsu and can only be given to you if Orochimaru bites your neck. This requires a canon rpc of Orochimaru. Characters that would already have it would be Canon Sasuke (Though he lost it later on), Canon Kimimaro, Canon Tayuya, Canon Jiroubou, Canon Kidoumaru, Canon Sakon/Ukon, and Canon Jugo (Since he was born with it). ONLY those characters can auto have the curse seal.