The Reincarnated Assassin is a Genius Swordsman

Briefly about The Reincarnated Assassin is a Genius Swordsman manga:

I was a chained dog in my past life. I didn’t remember my parents and I lived an emotionless life; like a tool. That life ended with my master horrifically killing me. I thought that was the end of my life. But when I opened my eyes again, I was born as the youngest child of the continent’s most powerful family. For both revenge and those who treasure me in my new life, I wielded the sword instead of the dagger.