I'm An Opportunistic Princess In-Charge of Solving Things

Princess Octavia was a high school girl until she was reincarnated into her beloved BL novel's world.The fact that she's able to see her brother, the main character, and his lover so closely is a good thing, but both of them are male.If so, won't there be trouble with future heirs?!There's no way they'll make her take a political marriage to offer them a child, right?!I don't want to be a character who's taken advantage of like that! If this is how it would be, I will surely find my own partner to be happy.....!!!