That Black hair boy is the ML, he is a Crown Prince and the main character of Novel
Really. Then it really is going to be more fun seeing Michael and the Crown Prince fight over our cutie Female Lead
Michael just see Jaina as his sister not in romantic way, but the Crown Prince have a rival but that shit dont count as a threat to him
Then, it's gonna be OK ...If that shit you're talking about is not a threat to our Crown Prince ...
Now, we will get to see the over-protective side of Michael if that black haired guy is the future ML and falls in love with our FL. I have a feeling that he'll say "You can't date at this young age of yours" and his inner thought would be like "I'll never let any men near my cute baby sister"