Responses
It's still ongoing so I'm not sure.
http://www.mangago.me/read-manga/bokura_no_negai/
oh those where choices but it was
http://www.mangago.me/read-manga/anitsuu/
im looking for a manga where this guy suddenly becomes the eldest or 3 brothers when his dad remarried and near the end, one of the brother kissed and confessed to him