Shikatari Nanatsuki traveled to the world of death and became the younger brother of the first captain Shikatari Takeunsai.

He thought he had a big boss to look up to, but he found out that Lu Qu Ba Yun Zhai was already terminally ill and would not live for many years.

Fortunately, he has awakened the teacher system, and he can become stronger just by teaching.

In order to gain the strength to gain a foothold in this world, Shikatori Nanazuki became a teacher at the Spiritual Arts Academy, and inherited the Shikatori Dojo, working hard to teach.

[Rokuguruma Kensei completed swordsmanship training under your guidance and received the reward - Sword Skill·Red Tide]

[Aizome Sosuke completed Kidō training under your guidance and received the reward - Hado No. 90·Black Coffin]

[Kurosaki Ichigo's strength increased significantly under your guidance and received the reward - Holy Word :D]

Many years later, Aizen Sosuke suddenly found...

"Dumbledore, hasn’t he already graduated? Why is he back at school?"

"Oh, Severus, don’t be so nervous. He’s the new Defense Against the Dark Arts professor!"

"Damn it! If I catch him using a cauldron to cook hot pot at school again, I swear I’ll duel him!"

...

"You are the worst class I have ever taught!"

"But, Professor… isn’t this your first class?"

...

"Miss Granger, as the study committee leader, you’ll guide everyone to read by the Black Lake every morning."

"Mr. Potter, as the sports committee leader, after reading, take them for a run around the Black Lake!"

...

"The countdown to the O.W.L. exams is 100 days!"

"Break the cauldrons, sink the boats—fight for full marks on the O.W.L.s!"

Douglas Holmes, a Hufflepuff with an Eastern soul, returns to Hogwarts three years after graduation to apply for a teaching position—

and brings a whole new style to the school.