Rather than yi forcing his feeling on A if the story went something like...
A parents tell yi to date as he's at the age of marriage. At first A feels weird then he see you agreeing to it. Then he watch Yi go on date with a women. He ignores this feeling as brother complex. Then when see yi seeing a women he feels jealously. Later consulting with his friend he realises his feelings aren't just brotherly love it's more than just that. Later he starts distancing himself from yi after realising his feelings for him.
After yi realise A is avoiding him he went to ask A about it.
After some drama Yi realises about A feeling for him.
Then slowly yi also fell in love with him.
But he's reluctant about it because of his parents.
The A talks to his parents. Make them agree about their relationship.
But parents don't totally agree about that.
And Yi is scared of disappointing them
If the story went like this it could have been more interesting and made sense in my opinion
I don't really hate the step sibling story. It might be because the step sibling stories are in trend right now that's why the author decided to add that trope in the story. In my opinion nothing wrong they're just following the trend.
But the actual problem is I don't see the chemistry between the step sibling
Author is just trying to force that trope between them.
Even if it's step sibling story chemistry between them matters more which matter of facts there's none between this two.
A and yi has grew up together as sibling. A always emphasized with Yi more as a sibling. Even when he got to know they aren't biological sibling. He didn't wanted to lose yi as his brother and tried to make it believe everyone that they're actual sibling.
Yi story doesn't make sense to me. He hated A when he was born coz he was afraid that their parents won't love him anymore thus he pretended to be a good brother just to fit in the family and then he fell in love with A? Doesn't make sense to me
His desire to protect A is more like brother complex rather than lover.
And his parents agreeing to this is weirdest of all.