I also want to know but seeing the red haired boy aura or his eyes i can already tell it was the ex of the mc... Maybe just maybe they're half brothers?
i think they are half brothers! since taeyoon's dad said that he could meet with his other dad which is referring to mc's ex. if its true that they are half brothers, thay is really fucked up ( ̄へ ̄)
In the 68th chapter we see baby taeyoon and red haired boy. What is the connection?