@Degernase The manwha pretty makes you infer instead of explaining it in like the novel.
But yes. He can replace skills. But, he has to keep: 24 hr return and Sword Master skill.
Every rank increase, he has gotten 1 increased skill slots.
@ReRead The penalty, right now, is recreating the pain and trauma that the enemy felt at their important life events.
It's op in the way that it does give away the enemy's history.