B is for Betrothed
Betrothed: engaged to be married.
…
Masako's father would often joke that she had a betrothed somewhere in the world, and that she couldn't marry anyone besides that person, whom he had already approved. When she was little, she always believed that she did have a betrothed, and she hoped eagerly for the day that her father would introduce them.
It wasn't until she was older did she realize that it was all a joke to keep her his little girl. Now she would smile, but it hurt more deeply than it should have.
Because now, she'd have to work to find somebody on her own.