Entanglement

Mai and her boyfriend, Tomonari Kasumi (known to The World as Sieg), are taken to a hospital due to both of them collapsing while playing a MMORPG called The World. Despite Mai waking up shortly after arriving at the hospital, Tomonari remains in a coma. For this, Mai is the object of rumors, especially when the clubhouse (known as G-study) is closed after the incident. It is soon revealed that she heard a certain sound (which is also present at important points in .hack//Sign) shortly before collapsing, and she later discovers that it is A in C major, which is used to tune instruments, including her violin. It was this sound that enabled her to wake up, and it was the first sound she made when she did. She meets Junichiro Tokuoka, and although she distrusts him at the beginning, as they investigate into Tomonari's coma, they soon become allies, if not friends. The investigation itself starts with Tokuoka accessing Tomonari's (Sieg's) account on The World, with Mai providing the password. Tokuoka accidentally opens the e-mail, and discovers that two users, Yukichin and Kyo, are close with Tomonari and have been harassing him with e-mails regarding his absence. It is also revealed during the course of the episode that Tomonari took the name Sieg as a contraction of Siegfried, from the German operatic cycle Der Ring Des Nibelungen, which was written by Wagner. Balmung is the name of Siegfried's sword, and Tomonari told Mai that he would become the possessor rather than the sword: a reference to the fact that he aimed to surpass the player character Balmung of the Azure Sky, one of the Descendants of Fianna. Tokuoka and Mai's investigation leads them to break into G-study, in order to attempt to recreate the same situation so that they can find out why Mai and Tomonari collapsed. The sound starts up again when they enter a field, and although Mai saves herself, Tokuoka seems to be losing it. In desperation, Mai destroys the monitor and (presumably) computer that they w