Let's be fr. Lee Geom literally got kidnapped, sold into s*x trafficking, r*ped, and almost k*lled multiple times. In Chapter 49 Lee Geom "chooses" Rieder to protect Wooyeon and everyone else who got involved. He is sacrificing his desires so Wooyeon can be safe.
If he's "irredeemable" for you, you didn't understand the story. Also, if it's any consolation for anyone who is confused on who the ML is, the creator reposts Wooyeon and Lee Geom together all the time on their Twitter. I've never seen them repost anything about Rieder and Lee Geom. If Lee Geom lives, I'm almost positive he will either end up with Wooyeon or no one.