What happened to beom seok? Is he a villain? Did the trio finally in good terms?

Beomseok was never an important character along with suho , they are core for sieun strong believe of what he is now, his past with them what shaped him. He completely destroyed beomseok but cherish suho and their friendships. The story in the first place isnt about the trio its about sieun slowly letting go of his past and embrace the new home to trust again (also the story about the union and all the issues) at the end sieun met with suho to finally heal himself