Responses
They were only raised as siblings for like 2 years then his parents died and everyone went to live with the family friend for 6 or 7 years. So it is not like he had a lot of time being a real brother, besides he never really acknowledged her as his sister just as someone his mom used to replace his actual sister.
uhm so he has a crush on his little sister.. be it adopted or not, they are still siblings and were raised as such so that's weird.