@Bruh I am going to disagree with you there. You seem to have read the novel of this series, which I didn't know existed and maybe the novel has more to it than the manhwa, but I am only going by what is shown in the manhwa.
The writing is quite bad, to start with. Dialogs are poorly written, the story barely makes any progress after almost 100 chapters, the world building is almost non-existent. For this to be a good slowburn novel about the regrets of the main character, it is a requirement to delve into his past, his mindset, to be quite detailed about what he went through before, what was he thinking and how he changed. None of it is in the novel. Not only do we know almost nothing about him, we don't know what he is thinking and we don't know what he wants. It's not in the manhwa, we are just guessing. All he does is eat sausages all day and that's it. Then he acts when he is "forced" to, but let's face it - he has no real reason to. This is not a behavior of a character who has a bunch of regrets.
The only thing I will agree is that the manhwa did show that he doesn't seem to care about his own life, but then he seem to be taking great care to live in comfort and have enough food to eat, to the point he is bankrupting the whole crew of the ship. What does he do with that regret of his? Nothing. A random act of kindness here and there to simply show he is maybe regretful - that's not a good writing.
I can keep going and write the whole essay about how bad this novel and main character is, but I will just stop here. I also looked up the novel and saw where this is going and I wanna that it makes no sense, which is the theme of the novel from the start.