
(Spoilers ahead)
I hope they will return soon. But their health comes first!!! Yes I would hate for it to be rushed or be dropped.
I know Sohwa is toxic and puts Miha through a lot but I am glad that someone else sees him as a victim as well. He was raised to be a criminal/gangster and seen how his father treated Miha. I do think Sohwa is conflict like when he goes to put the blanket on Miha but tosses it instead. His father created Sohwa and imprint his hate on him. But some of it is Sohwa. He does not like when Miha is scared of him or afraid of touching him. He gets mad and reacts violently scaring Miha even more.. I bet he would not be acting that way toward Miha if his father did not imprint the hate.
Sohwa, asked his father about getting everything he own once he got married and asked about Miha with a blush. He has a crush on him then. Maybe wanting to marry Rihan to get Miha was his idea back then? Seeing how Miha was more of object to his father
I think there is a possibility that Miha is not related to them.
“From Miha's POV, Sohwa appears to have started abusing him after Rihan left.” I think I got this impression as well. If this is true Miha loved Sohwa before the (sexual) abuse happened. He has been jealous about how close they have been but they have been on bad terms currently. I think I get the impression that Rihan and Sohwa has something but at one point it revealed Sohwa loves Miha more. My current understanding is Rihan was actually a replacement for Miha, in ways.
I had also thought he was faking it because their are moments where he acted like his old and how he “knew” things. He did have generalize amnesia, which they can have some Memories or lose them all. He had to have some for how he know he and Miha has sex before and his affect for Miha.
In chapter 21 we learn Miha is 28. I seen a Spanish summary stating Sohwa is 8 years younger. Wait! Miha birthday is January 1. Making Sohwa 19 at the beginning and turn 20 in chapter 5. If he has been sexually abusing Miha since Rihan left.... Miha would had been 25 and Sohwa 17.
He does not fully understand relationships and probably don’t know how to express himself with how his raised. Some of his outrages is him not knowing how to handle himself and being insecure.
He has been excessively and obsessively watching Miha. I don’t know if it is a hint of hope but when he regained all his memories. He probably remembers the last two weeks of Miha being different toward him and his ego grow and he expects Miha to return by himself not realizing Miha was being crushed. Oh in Korean and Spanish version Sohwa’s last line before Hyung is a question. English has it as “you like it when I act like a kid.”
It is suppose to be “you don’t like me when I pretend to be a child.” We don’t know how Sohwa would has reacted to Miha afterwards but we may never know one for the author Health and the story seems like a few things are going to happen before They meet again.
The description of the summary says however, an incident takes place that helps Miha and Sohwa to reflect and figure out what they are feeling for each other. Was Sohwa being stabbed that incident? Or has it not happen yet? For Sohwa to snap of how he has been imprinted on maybe someone bad has to happen to Miha before he understands? I don’t know.
I feel like Sohwa dislikes How Miha acts but repeats the same actions to get different results. I think that is a sign of insanity! But maybe he will reflect on those two weeks and learn how to treat Miha better.

I think you hit the nail on the head with your comment that Sohwa doesn't understand relationships and doesn't know how to act.
The environment that both Miha and Sohwa had been raised on and the expectations (or in Miha's case lack of expectations) put on them have shaped them to be in the situation they are in.
Miha is going to grab on to anything, even the little crumbs of affection, he gets from Sohwa.
Sohwa on the other hand is expected to take without a thought or apology because that's what is expected of him as a crime lord.
He has only seen Miha being mistreated by everyone so he does it too. He wanted Miha but it never occurred to him to court him like he did Rihan, maybe because he feared he would refused because they were brothers or maybe because Miha's feelings were always there to be disregarded.
I am not suggesting Sohwa doesn't have any responsibility in what he has done. But rather than just insane I see him as someone that f'ed up royally, doesn't see a way out and keeps bluffing his way out. Instead he just keeps digging that hole deeper every time.
The conflict he feels in regards to Miha seems to be due to his belief that he cannot fix what he destroyed.
Maybe I am reading too much into chapter 16, but that whole inner monologue to me seemed to show the two trains of thought warring inside Sohwa but when he gets his I memories back we also see how Sohwa chooses to deal with these thoughts. He will bulldozed over his conflicting feelings and Miha's if it means he can have him.
I also agree with you that Rihan is probably the replacement for Miha (he even had his father's approval for him and all that), that why Miha's unreliable POV is important here.
Sohwa appears to be operating under the belief that everything is hopeless with Miha so he rather force him because he cannot fathom that Miha could love him after everything Sohwa has done to him (actually this is a very logical response).
Miha, on the other hand, has gone through so much abuse and made to feel so worthless that he has attached himself to Sohwa, despite what he has made him endure.
I had not caught Sohwa's age until you pointed it out either. I knew he was younger and this seems to be one of the few mangas that actually reflect the correct age difference in the flashbacks.
The age difference is a big component too. Sohwa, a boy that gets all he wants without questions and whose worst instincts are being nurtured by his father, has the added recklessness of being a thoughtless, aggressive teenager.
Miha may be older but he doesn't have any defense to wield against the little savage prince. He is horrifyingly accustomed to being mistreated and his only defense would be to be submissive towards the abuser.
I think Sohwa, as he was during his amnesiac state, showed the sweet boy he used to be at least towards Miha because this state erased all the preconceived notions he had about Miha from before. It erased their past and all he knew was his sincere attraction for Miha. He wasn't even bothered by the fact that they were brothers.
Not having his love and the thought of Miha leaving him brings Sohwa over the edge. I feel like this is what keeps Sohwa in the borderline of insanity, mainly due to the blind spots in his thinking.
I think Sohwa is maturing now but cannot deal yet with the gravity of what he has done and the thoughts of losing Miha.
I hope this story goes on...
Some thoughts (Spoilers ahead)
First off, I wish the very best to the creators of this story. Their health issues appear to be very serious and here they are working their bums off. Really outstanding people.
In that note, I would hate to see this story rushed or stopped because of it but I would understand and support them in their decisions. Please support this story if you can. Thank you.
To my thoughts on this story.
I completely blame Sohwa and Miha's father for the situation his sons are finnding themselves in.
It is pretty clear that their father's hatred of Miha is a complete projection to his hatred/feelings for Miha's mother.
Miha has not even had the opportunity to develop a personality to cause the level of hatred his father exhibits for him. All Miha can do is try to make himself as unoffensive, submissive and bland as possible to not cause his father's ire.
Yet nothing he does gets a positive reaction from this man. Everything offends him, to the extreme. Everything make Miha too low to be acknowledged. He is treated as trash, called it in multiple occasions.
All Miha's father sees is Miha's mother in every action, word and look. Miha looks like her so her "flaws", her "traits", her "crimes" are all Miha's. He doesn't need to commit them, he is guilty simply from coming from her womb.
Sohwa sees all this from a very young age and understands it as this being the way that things are supposed to be.
Sohwa is shown to us as a very confident and very affectionate child who is being very deliberately groomed by his father to take over for him in a crime syndicate.
His father nurtures the things he likes about Sohwa and that he sees are a reflection of himself. That also means he makes sure Sohwa has all the callousness and cruelty required for his future job. Whether, this is something Sohwa displays as a child or something all children display at some point (pulling the wings off a bug) we might not know but his father knew he needed to feed that impulse because it would be a helpful trait for Sohwa later in life.
Sohwa, on the other hand, probably loved his older brother as a child but did not understand what brotherly love was. His father treated Miha as something "worthless" of affection, care, life, and decency.
This is reinforced over and over again to Sohwa and he is encouraged and expected (whether told to or not) to do the same.
So Sohwa eventually finds himself twisting those feelings he had for his brother to sexual possessiveness. Abusing Miha is the acceptable physical contact according to their father's logic and for Sohwa, it turns into sexual abuse of Miha because unlike his father he actually held affection for Miha.
Don't misunderstand me - this is twisted - not an excuse.
But the way I see it, his father HATES Miha, cannot abide him...but Miha is his blood. So he holds a certain responsibility, which he resents bitterly, for Miha. I am sure he didn't kick him out before Sohwa was stabbed because he didn't want to take Sohwa's plaything away. He detests his oldest son for whatever sins his mother did.
But Sohwa loved his brother yet he didn't understand that was a normal feeling to have because he had been told Sohwa was unworthy and beneath him by the person that he admired and worshiped - their dad. If their dad doesn't love Miha, then something must really be wrong with Miha. I also don't think he understands there are other types of love other than those with a sexual component to them.
From Miha's POV, Sohwa appears to have started abusing him after Rihan left.
He said that he always thought he was some sort of poor substitute for Rihan because as he understands it, Rihan left to study abroad as a refusal to Sohwa's desires to move to an intimate relationship.
Miha also confirms his feelings were twisted to love for Sohwa after having suffered through their encounters at the beginning. The relationship has always been forced but now, for Miha, is has the extra f'ed up component of having turned into love for the abuser.
I think that Rihan leaving was the catalyst (the excuse at least) for Sohwa. I am not sure he didn't start "substituting" Rihan with Miha before this but I think that it definitely gave Sohwa permission to do as he pleased with Miha because he felt he lost Rihan and he could take it out on Miha unquestioned.
But Sohwa also confirms as his memory returns (up to that point, I thought Sohwa had been faking his memory loss) that he loved Miha but he (Sohwa) had ruined things between them and there was no way to fix it (no turning back). So he kept going and kept telling himself that Miha was a toy that he would get tired of someday.
Sohwa forced himself on Miha and by the time he realized that, no, Miha wasn't a toy and that he was, indeed, now in love with Miha and not Rihan, that Miha wasn't a placeholder or a practice toy to take his frustrations on, it was too late to fix things. He had done to much damage that he sees as irreparable.
Look at how enraged he became when he discovered that Miha was in the process of leaving him. How he looks at Miha's reactions when they are in the act, even in the first chapters, he is aware of everything Miha does like he is obsessively looking for a hint of hope.
He is livid when Miha pulls away from him, or when he doesn't reply that he loves him (and I thought it was because he was blind to what he was doing to cause Miha's reactions but he is fully aware and lashes out because he sees their relationship as hopeless - through his own doing).
He knows what Miha likes and doesn't like. And Miha isn't aware of it. He just keeps on calling Sohwa's kindness.
The only thing he doesn't allow himself to see is that Miha, despite Sohwa's treatment of him, actually loves him. Sohwa can't see that because he feels guilty of what he did and hopeless that he can fix it.
But he can't let Miha go. He would rather keeps things as they are with Miha hating him as he believes than not have him. The entire scene when Sohwa gets his memories back shows you his way of thinking: his guilt, his despair and his choice to have Miha at all costs even if it hurts Miha, even if Miha hates him.
I think Sohwa as he is now and he showed it while suffering from amnesia would not care about his father's approval or opinion if he thought he had a chance with Miha. But as a child, who worshipped his father and had a very limited view of the world, he did so much damaged to his and Miha's relationship and then crossed a line he can't turn back from.
The child Sohwa could have always stayed a brother with Miha if not for his limited exposure of the world but the person he became broke those bonds forever.