The answer is: "OST song" refers to the song in the OST. OST referred to the original music in movies, TV series, and other film and television works, and the song part was the OST song. According to the search results, some OSTs of movies and television works included some songs, such as the theme song of the TV series OST of " A Thought of Passing Mountains," many of Zhou Shen's OST songs, and Yu Kewei's Top Ten Classic OSTs. Therefore, an OST song referred to the song part of the original music in a film or television work.
Blade Fangs was a Japanese manga created by Itagaki Keisuke. There were four works in total, namely Grappler Blade Fangs, Fanma Blade Fangs, Blade Fangs Path, and Blade Fangs Path 2. The theme of this manga was hand-to-hand combat, and it told the story of the young Blade Fang fighting with strong enemies in various underground arena competitions. The characters in the Blade Fangs series had distinct personalities, compact storylines, and unique styles. This series of comics was well-known in China and was welcomed and loved. The animated version of Blade Fangs also had two seasons and could be watched online. As for the viewing order of Blade Fangs, they could be viewed in the order of Blade Fangs 1, Blade Fangs 2, Fanma Blade Fangs, Blade Fangs Path, and Blade Fangs Path 2.
The OST lineup for the second season of Celebrating Years had already been announced. Among them, Li Jian sang the theme song " In My Lifetime," Zhou Shen sang the ending song " Excuse me," Liang Long, Liu Duanduan, Zhang Haowei, and Guo Zifan performed the promotional song " Aiya." These songs would bring more musical elements to the second season of " Celebrating Years," adding more emotions and atmosphere to the plot.