Well realistically. Yohan is only doing his job that he was told to do for his brother.
It’s not his job to worry about whether or not Victor gets attached. No real reason to be disappointed in him when he’s only doing this to save his brother. Besides I’m sure they’ll find a way to work things out.
** THIS MAY CONTAIN A SPOILER BCUZ ITS A THEORY OF MINE
Actually I think yohan’s brother might end up dying or disappearing like their parents, so that Yohan doesn’t have a reason to be a spy anymore. Or something else may happen. Who knows
PLS his brother disappearing or dying hurts even more *sob*
But Yohan is developing feelings for Victor as well. Allowing his feelings for Victor to grow knowing he'll have to betray him is setting himself up for pain. Even if Simon dies I'm sure Victor will find out what Yohan's true intentions were which will hurt Victor. I know this is just a story and they'll end up together despite this, but it'll hurt to read once it happens
I am a little frustrated with Yohan to be honest. He knows he'll ultimately have to betray Victor in order to save his brother yet he continues to let him and Victor emotionally invest in each other. Yohan has learned that Victor is not the person those rumors have made him out to be, but is actually a good person (from what we've seen at least). I am not looking forward to this all coming to light and seeing Victor hurt again.