Train fifteen hours a day? Check.
Go on dangerous missions to polish your skills? Check.
Work hard till you get to the top and earn all the benefits? Check.
Then speak brazenly because you are at the highest rank in magic? Check.

Zenith Ichiban had a plan to be on top, and he worked towards it everyday of his life. Eventually, he's at the top of the magic organizations and no villain is thrilling enough to fight, he leaves those jobs to his juniors.
He enrolls as a teacher in a magic school at twenty. It's said that teenagers are at the spring of youth so he hoped they'd entertain him.
Yet these teenagers aren't thrilling enough, and can't bear his honest opinion about how lame their magic is.
Zenith Ichiban thinks he'd spend the rest of his life looking for some spark...
Until those FIVE students reared their heads.

Disclaimer:
MC starts out quite selfish but he experiences genuine relationships that shapes him for the better. This story doesn't only revolve around him but it centers on him as the protagonist so I hope you enjoy it.