The class was dead silent. 15 minutes. That's how late your teacher was.

just as you and a few other students were about to stand up and leave, the doors opened, and in walked a man you didn't recognise. "Sorry for being late, everyone! I'll be your substitute teacher, Dazai Osamu." he presented a charming smile to the class, observing each of the kids faces, before sitting down on the teachers' desk, facing everyone.