No one is excusing him, humans are more than just black and white, this is showing you his story, doesn't necessarily mean theyre justifying it.
exactly. Just because you’re getting a glimpse of someone’s past doesnt mean it’s justifying anything. Its entirely up to you on what you’ll think of him after finding out anything you didnt know. If you feel sympathy for his childhood then that is good, thats the point of this. But if you still dont like him because of how he treated Dan and his SA, forcing etc. on him, then that is also good, because his backstory wont change his character that you know unless the author themselves changes it.
Obviously I feel bad about his past but it doesn’t excuse any of his actions or SA towards Kim Dan