Suree , Rohee is the white hair guy who's inlove with MC . He switched bodies longgg time ago with director yoon . So from the start of the story , the one who's been flirting and chasing our MC is actually Rohee , not director yoon
If you want to understand more :
i'll explain the important part from the start . So in this story , MC , Jintae and this Rohee guy (white hair) is immortal being and is friends since theyre being capture/experimented on tgt . When they escape the lab tgt , the 3 decide to live tgt . Rohee , is inlove with our MC , but unfortunately MC likes Jintae . So when Jintae got a lover who tried to poisoned MC , MC decides to leave them bringing rohee alone . But that damn psycho jintae wont let them and made his lover poisoned Rohee too , so they cant leave , MC begged Jintae to save Rohee and when when Jintae gave in , and went to get the medicine far away , MC got rid of his lover by having their worshipper eat the lover saying it would give them immortality , thats where the tradition of eating ppl start fro the firebird cult . Jintae got angry and MC felt guilty too for what he did , so to avoid more pain for both , they hv Rohee erase their memories of the incident every ten years , so they basically forget each other while only rohee knows the truth . So time and time again , Jintae and MC still somehow like fate still be around each pther and every time , MC fell for him until their memories came back after 10 years due and rohee erase it again . But during the previous life time is where director yoon got sacrificed to the firebird when he was young , and MC and jintae save him , But Jintae cajnged his mind the last minute , cus he doesnt want director Yoon to grow up and fall for MC (cus Jintae's freaking psycho) so he try to leave director yoon , only for Rohee to be the real one who save director yoon . Soo then , to help director yoon with revenge to the firebird for almost killing him , Rohee offer to switch bodies with director yoon . Soo this whole time , the one who's in director yoon's body is actually Rohee from the start , all the flirting and chasing is all Rohee ! And the one in rohee's body is actually director yoon . Thats why he didnt remember much who MC is (pretending probably) .
Yup , lol . So remember in the story part where MC's company was suppose to give money to this other company so the other company can pay their debts and pay their workers after bankruptcy ? The other company is actually owned by director yoon's father . And there was a chapter where little yoon went to MC's house to beg him to help his father , thats where they met and MC promised to help him but yoon's parents still end up dead by loan sharks bcs of the debt . Director yoon , who became orphan was then took in by the firebird as a sacrifice . Thats where MC who felt guilt for yoon's parents death , help Yoon escape for the place after setting it on fire (where they held the sacrificial ceremony ).

The plot twist over plot twist always surprised me . But i was right when i predicted , The ML was actually Rohee , Im so happy abt it :)
Although alot dont agree due to the plot twist , understandable tho , cus For me its easy to understand cus i read it whole in one go , maybe most are reader who read it when it was still updating/ongoing thats why its harder to keep the plot memorized .