So I know that it's a father and son. The father retired from the military when the rest of the family is killed.the son inherits the family business and Fortune. Including a hotel where he does a photo shoot in the bathroom with a hotel manager's daughter. And somehow ends up in an Asian country with a sword to return to the emperor. Also he knows martial arts and is called a samurai at some point in the book I think.
Random things I know but it's bugging me to not be able to find it and re read it.
Any help would be appreciated