ML or SML Forced to Agree to Marry a Secondary FC

ML - To protect the FL. Not consummated.

The ML has two children with a mistress before falling for the FL. The FL also accepts a concubine into their household after she and the ML are married. That relationship is never consummated. 

The SML is forced to marry a Princess instead of the FL in order to protect his family and (to a lesser extent) to protect the FL and her family. 

ML - Concubines before meeting the FL. Not consummated.

Also the SML in a way, but it's complicated.

SML - To protect the FL. Not consummated.

ML agrees to marry his deceased ex-girlfriend's younger sister who threatens (through a manipulative friend) to kill herself if he does not agree. 

ML - For the good of the nation. The FL also marries someone else early on. The ML returns to the FL in the end when his son is old enough to inherit the throne.

ML is forced into a political marriage before meeting the FL again when they are adults. Not consummated.

The ML agrees to marry his childhood friend who is in love with him in order to protect his family's company and employees (and his father who is in poor health). The FL tells him to go through with it. The marriage is not consummated. Ultimately the SFL agrees to a divorce. 

ML is forced into an arranged marriage before meeting the FL. Not consummated.

ML agrees to separate from the FL and govern the country + marry another for the good of the nation. Sees the FL again on his deathbed. 

ML agrees to marry another woman to protect the FL's secret. SFL calls it off.

SML