 If you liked
Ookami-heika no Hanayome
|
 ...then you might like
Kuro Hakushaku wa Hoshi wo Mederu
|
In both mangas, a poor girl is picked up by a rich (royalty in Ookami-heika) person, and must act as their fake wife. Both have similar relationships, as they cannot fall for each other (however, in Ookami-heika, the girl eventually falls for the male, but in Kuro Hakushaku wa Hoshi wo Mederu their relationship has not developed enough). However, in Ookami-heika, there wasn't really a specific reason as to choosing the girl, whereas in Kuro Hakushaku wa Hoshi wo Mederu, she was chosen because she was a dhampir, and the male wants to keep an eye on her.