more like using him perhaps, since he needs him for his own health and is rough with him, is more like, not letting you till satisfied
He has broken up his defenses as in the walls he put up since he’s used to distancing himself from everyone due to how nothing good happens from staying with him for long until the mc came into the picture which is his now lucky charm since mc’s curse that corroded him got passed onto him from their past life and now he’s the one being corrupted. Seeing how the mc is fine and seems to like him too he had begun to learn to hold onto something with the comfort of it not breaking
Probably. He saw no point in getting close before because he's a mess, with all the things going on (his family situation, his mental state, etc). Now that his attempt to stay away from Sajun has proved to be a worse choice for him (physically and mentally) he has chosen to accept Sajun in his life.
So by "never let go" its not in a sense of "not letting you go tonight" right? But rather " Im not letting you go, you're mine now forever" right? Sorry english is not my first language