In the Ep. 4, Kim's board was not in the book. That's the series adaptation... so we would have to see how the series would take us. Kim never did any of the investigation in the books. He was as perplexed when K.Korn and K.Kun reviled the true about Porsche's and Chey's parents. Kim and Kinn were on their knees... both brothers shook and turned pale.
Another series adaptation... In the novel, PETE was the person who handed Porsche the condom bag, NOT BIG, and sent him into Kinn's room to learn Kinn's sexual preference. Porsche has been going around testing his theory of grabbing and asking strange questions... So Pete did that... so that Porsche got his answer + fun for Pete. ... I think the series are trying to preserve Pete's angelic character and I don't see a big different in the change. Pete told Porsche that he had to use the bathroom and asked Porsche for a favor to deliver the bag. Porsche walked in with his no-knock policy and saw Kinn's lover naked on his laps.... I didn't see a big different... What the series did works, too, for me.
Adaptation of the sex scene is, too, there. It looked A LOT more like a true consent in the series. It was a consent in the novels... but it was a big different. Porsche didn't want to go through it and he was in a great pain.... I think the series did a good job of divergence... People would NOT have accepted the novel version of the story on film... GHB doesn't do what the series actually showed... We people who understand the drug know that... GHB makes you consent by force; not by suggestion... the authors understood that, too. SO in the books, Porsche consent because his body was gonna explore... he could die if he was left in that stage... therefore, he had to consent. In the series, Porsche seemed more like he was drunk and wanted to sleep with Kinn... Porsche wasn't in pain.... again, I think it is necessary for the series to take that route... it doesn't bother me as much.... the mermaid scene bother me a great deal! LoL!
In the novels, that was real turn of their relationship... Porsche was in agony. He was in pain during that night and days after. Kinn took him to the hospital the next day because Porsche wouldn't stop bleeding. Porsche had bad fever until he got to hospital after the wood... It would have been 2 weeks maybe...
I got an impression that K.Korn thought that Kim could win if he was in the race. In the novel or recap, Kinn explained to Porsche when they were in the wood, why he put all the burden on his shoulders. Kinn thought that no one would do it... Tankhun didn't want it. Kim was never home. How would his father feel if he couldn't rely on anyone... so he was trying to be that person for his dad and family.
Wait... What was the question, again??? Anyway, I hope that I helped answering your question... :)