I get confused with ML's name. Can anyone please tell me what is his name exactly?
Yup, Woo Ah-seong (or Ah Seong or Ahseong or Aseong, depending on how you romanize it). Like you said, the -ah is added to the end of his name because the MC and ML are friends, but it shouldn't remove the initial "Ah" syllable from his name, so the friendly way to call his name would be "Ah-Seong-ah" (아성아). This is how the MC calls him in the original Korean version.
The novel is soo beautifully written. It bring such a rollercoaster emotions. I cried my eyes out the entire time. It's so deep, yet still entertaining. The best koeran's novel i've ever read wish the manhwa carried it out well..
*still wish more for their scene together :')
https://www.patreon.com/collection/188783
I'm pretty sure you'll enjoy it
Is the side stories a "what if" stories?