Ok here is my theory: Haesoo will choose Taku, but he's still in love with Joowon and Taku will realize it. So seeing how unhappy Haesoo is, he will let him go because Haesoo can't do it himself. That's it
Isn't taku want to get rid of joowon from haesoo's life? He said that
"seeing how unhappy Haesoo is-"
Ok here is my theory: Haesoo will choose Taku, but he's still in love with Joowon and Taku will realize it. So seeing how unhappy Haesoo is, he will let him go because Haesoo can't do it himself. That's it