So... The duke is a scumbag who are "cheating" with his lover for 9 YEARS, and once he had enough, he choose to put the "blame" on FL to make himself looks good saying she is being unfaithful and evil (talking about the pot calling the kettle black).
Wow... That is low even for shitty "Male Lead"... and i read "Cheating Men Must Die". I know how low shitty "Male Lead" could be and saying this guy is low says a lot.