@ringoahiru you ask for it. I did my best but I stoped reading the novel in the 700ch almost three years ago(shame on me, yes.)
Choi Han is an absolutely sarcastic asshole with no chill, and Alberu vibes with that even if he shouldn't because he is like the crown prince. Like, Choi Han would tell a noble to shut the fuck up, and Alberu would just gaslight the poor man into thinking he said nothing.
They are the type of friends who absolutely roast each other with no hesitation. They are like:
Choi Han: morning, fake ass prince. How was your day? I hope bad like your hair style.
Alberu: *not missing a sec* Good morning, overrated stinky dog. My morning was good until I saw your ugly face.
And Cale just learned to not try to understand them anymore. He is sitting there, looking at them, eating cookies, and thinking, 'They're such good friends, bc he has a distortion of the concept of friendship.
And their bond activity is just fucking with Cale until he looks like he regrets every decision in his life. Alberu and Choi Han agree that he looks one step closer to committing first-grade murder and is the most hilarious shit ever.
Alberu: hi, old man, How was your day?
Choi Han: dunno, how was your day, Cale-nim?
Or,
Choi Han: the other day I was thinking-
Alberu: do you think? I thought domestic dogs didn't
Choi Han: *not even blinking*-is Cale-nim the protagonist of a reality show for the Ancient powers?
Alberu: holy sh-
*Cale with his eye twitching as his only reaction, plotting how to ruin the rest of the week of these motherfukers*
But at the end of the day, both of them know deep down that if something happens to the other, they will throw hands with the gods if it is necessary.
Choi Han would punch some Nobels without a thought in his mind if someone insulted Alberu, and Alberu would ruin the life of the first idiot to say something about his Instructor-nim. They love each other; they know it, but they will rather kill themselves than say it out loud.
My headcanon is that Cale has a deep deep voice and not naturally but more because OG!Cale was a alcoholic and his vocal chords are fucked up.
So, like the Gen Z that he's, he makes the "Hello, baby girl" to Choi Han because is the only one that will understand it (bc Choi Jung Soo memories). It goes like this:
Cale: *walking into the room and with the most deadpan face he says to Choi Han* Hello, Baby Girl *and walks out*
Choi Han: ????? *confused noises bc low-key that was actually good*
Cale: Why is there air conditioning in hospitals?
Choi Han: I dont know, why?
Cale: To keep the vegetables cool and fresh.
Choi Han: *snorts*
Cale and Eruhaben were drinking quietly when an exited Raon enters the room flying.
“Goldie! I have a question! The intelligent Rosalyn told me that sometimes new stars born and others die, but, how they die?”
Before the gold dragon can even process the question, Cale responded without hesitation and almost seemed like reflex a response when his face didn’t change.
“Usually an overdose”
Eruhaben snort without grace and Cale suddenly realizes with horror who he said that answer. There's no way he's gonna explain what that means to Raon.
"What do you call a dog with no legs?"
Cale suddenly broke the silence in Alebru's office with a emotionless voice.
The redhead was lying on the sofa and did not look up from the documents with which he was helping the blonde
Alberu rised his head from his own documents, confused by the question without context.
"What?"
"Doesn’t matter what you call him, he won’t come anyway."
Cale grins when Alberu chokes and keep reading the documents calmly.