It's been explained in the beginning of the story and there are so many context clues on why luan acted the way he did i love that this story made the mc complex, luan has been forced into assuming his older brother's role as the next heir whom was pretending to be sick so he can avoid his duties, ever since then all eyes are on him and has been expecting him to behave and walk the path that was paved for him even as a child he knew that he was just being taken advantage of, his only solace was when meeting clauden to which he experienced freedom, love and being normal
Then he's also deceived to go to a foreign country "so that he could be with clauden" a hollow promise told to him by the butler believing that it was just a childhood memory that he will grow out of (to which he didn't) and i think that it truly is love for him to be able to keep that for 11 years and which people are underestimating causing luan to go mad and frustrated that no one is taking him serious
And lastly when he came back and looked for luan all these people who are blinded by money are now taking advantage of him and someone who looked like clauden from his memories literally did deceive him and left luan upset, frustrated and heartbroken and losing trust to everyone claiming they were his childhood friend, he got news that clauden left town and didn't wanna accept anyone who will claim their identity and that's when the actual clauden came barging but since luan is disheartened and lost faith he didn't wanna look into the face of the man and in the moment of passion then ordered for clauden to get beat up, he didn't know it was him and he thought the flower was a fake since it was broken and in pieces it's really not that hard to get that and think that this story is relatable and realistic.
im sorry but i just cant enjoy this, i just cant get myself to read the sides. im so so so mad the the mf blonde idgaf about his name cause im so mad. he himself doesnt remember shit about their childhood, and he recognised someone else as Claudent. then when Claudent actually shows up, claiming facts and even showing him the flower thingie he had so many years, HE BEATS THE FUCK OUT OF HIM? WHAT?? AND THEN HE FORCES HIM TO COME TO HIS MANSION AND STAY WITH HIM WTF NO? NO THIS ISNT FAIR. BECAUSE OF YOUR STUPID MISTAKE WHY SHOULD CLAUDENT SUFFER NO NO I WAS ENJOYING THEIR PAST BUT TBH THE BLONDE DIDNT EVEN REMEMBER SHIT AND ITS SO ANNOYINGGG WHY