Having read this chapter in the novel, still can’t make out what the hell Cale and Choi ...

The main point is Cale said that as long as Ron still his butler then he is just a butler for Cale.

Choi Han is basically warning Cale that Ron is strong/dangerous and that Cale should be cautious of him. Cale then pretty much says he doesn't care because whether Ron is strong/dangerous or not it doesn't matter in their master/butler relationship.

Choi Han said to Cale that Ron is a dangerous person, he has a blood smell means that Ron is used to killing, Choi Han / CH thinking that how could such a strong person by Cale's side but he never helping Cale in some task, like helping the dragon (actually Ron in the novel is always worried of Cale's situation but in the manhwa it's not really detailed, like the one in the dragon rescue he actually waiting Cale in front of the door, same as how he waiting him until late night when Cale got the shield, so he has two theories, one is that Ron hiding his capabilities to Henituse fams, or Cale himself is the one that didn't trusted Ron, so he said to Cale to be aware of Ron, but Cale is being Cale said nonchalantly to CH that both of them is the same, has blood smelled but didn't do any bad to him, Ron as the one who heard that is quite shocked in the novel, that's also the same with CH, that's why CH said in the novel you heard him right, you can't follow him and Ron really didn't follow his puppy master XDD