Tang Zong said to Lin Bai furiously.
Lin Bai turned to look at Tang Zong and, with a sense of helplessness, clasped his fists in greeting, "Senior Brother, greetings."
After the greeting, Lin Bai did not wish to pay any more attention to Tang Zong and turned his gaze towards Gu Yueqing, not even bothering to spare Tang Zong another glance.
In the Martial World, there exists an unwritten rule known as "respect your seniors," which means no matter the age of the other person, if their cultivation is higher than yours, if their strength is greater, you must address them as your senior.
Since Lin Bai and Tang Zong were both disciples of the Sword Art Academy, and since Tang Zong claimed to be of higher status and stronger than Lin Bai, it wasn't improper for Lin Bai to address him as Senior Brother.
Moreover, although Lin Bai wasn't born into a scholarly family, he still understood the principles of courtesy.