Sword Art Online: the Promise in the Old Save

Using the "official linkage bracelet" that fits the world view of the entire "SAO" series as the core carrier, it connects Kirito and Asuna's cross-world bond spanning five years. From the neural resonance of the bracelet in the library to awakening the first-generation archive, to the rising sun in Rulid Village, the AR linkage in Akihabara, the revelation of the heart at the ALO wedding venue, and the formal confession at the observation deck, the two used the bracelet to unlock unsent messages, repair neural faults, and synchronize virtual and real daily life, making scenes such as SAO's Aincrad, ALO's Nausicaa, and Underworld's Central Cathedral an emotional bond.