I actually think the person jae ha was running after in chapter 14 was yeon ho from his timeline and in last few panels he suddenly stops as if he saw someone familiar it would be the adult yeon ho, also the adult yeon ho suddenly starts running(in chapter 13 i think) when he sees the person across him who have the same hair colour as jaeha so even if its impossible I think both the timline merged ig if thats the right word.
I haven't started reading it but is is there a love triangle?
Nope
yesn't
No there's no love triangle here
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