Sebastian didn't waste a single hour. In a week's time, he tortured and punished the man and only stopped when Magnus told him to rest.
By the seventh day, he felt his mind became clearer and his body lighter. Hatred started to be cleansed from his heart, not only because he took his time punishing the evil but also because he hung out with the Apostle himself for a week.
Magnus wasn't a normal guy, but not in a bad way. He was certainly not your typical teenager. He was very well-read, very just, had a very high moral ground, but also relaxed and cheerful at the same time.
13-year-old him was able to recite any scripture from memory and not forget all of the law and military books the empire had. He recited poems, quoting philosophies, and was generally a great and witty guy to be around.
He was a prince to the bone, a man with an unbound future.
And that week was the only time Sebastian could laugh and joke around like a normal teen.