The Guardian Knight Couldn’t Protect His Lord

I could not protect him.

I am a failed guardian knight.

Then a second chance came to me: regression to five years ago.

The body of the youngest young master, who died young at fifteen from a rare illness.

Why him? No, actually, this is better.

"Hah, the body of the greatest genius in the family's history."

This life will be different.

Everything that threatens our young master, I will crush it.

The source of the crisis, and the source of the source of the crisis, all of it. I will crush it all.