You need to have a particle in the original English if you want the translation to be as accurate as possible. "Chi no Ou" is the most accurate translation I can give you.

If you want the title to be written in Japanese, then I suggest writing it in Kataka and use the English words as it is. ブラッド・キング This would actually be far better than translating it.

well i wanted it as a title if that helps, and thanks so far, you've really helped me out. thanks a lot you guys, i really appreciate it.
hugs and thanks

Ousama is also king, and blood can also be read as chi.

It really depends- does she want this as a name, or a title?

I would say Ketsueki Oushou; ketsueki = blood, while Oushou = King

.... however, there may be a better translation, if anyone else comes up with one/suggests another one.