At the end what did Ji-hyun mean when she said she thinks she met a man from the future your future? Was she talking about the old man she met at the tree 3 years prior or the guy she was in love with that died? Was the old man at the tree the adult version of Kyun-woo? Also if Ji-hyun was conversing with the mother of the guy that died at the end and his mother is also Kyun-woo auntie then we're they related?
shareYes. As you can see in Trivia, the old man is old Kyun-woo in fact.
And yes. Kyun-woo and The Girl's late boyfriend are cousins.
Use spoilers by the way.
"After The Girl talks to the old man for the last time, as she looks off into the sky, a small U.F.O. hovers across and zips off quickly. It has been said that the U.F.O was actually a time machine that Kyun-woo, as an old man, used to revisit his past. The old man also made a brief appearance near the beginning of the film, when Kyun-woo and The Girl meet for the first time. "
i re-checked that scene. yes, indeed she sees an UFO flying away while she is standing under the tree with his letter in his hand.