It was bothering me because 55 seconds into hearing it, for jingoku sensei nube 55 seconds in the intro they use the William Tell overture after 1min and 55 seconds
https://youtu.be/c7O91GDWGPU?=tJtS0WPFAvtuczSU
then hell teacher nube
https://youtu.be/493DJEmz8Yc?=Lu0Jt3_4fpBB_KGz