Ansatsu kyôshitsu / Assassination Classroom [Anime]

For those with a high level of aptitude… The sooner they know the frustration of defeat, the greater their growth will be.

Sometimes the strong and the weak can switch sides, just like that. But staying in the strong camp... That is the hardest thing to do.

Whether a fish lives in a clear stream or a water ditch, so long as it continues swimming forward, it will grow up beautifully.

If everyone wants to kill you, — it means that they recognize your strength, that's the thing.