Ryuuichi is as cold as ice. He is willing to use and abuse other people to achieve his personal goals, solving all problems that arise either with money or his fists - and he is never satisfied. No matter how much money he gets, no matter how many girlfriends he has, he always feels like he can do better. Eventually he decides to leave his home town and live in Tokyo, determined to work his way to the top using any means necessary...
Duke Tougou - otherwise known as Golgo 13; he's loved by the ladies, hated by his enemies, is enamored with firepower, and can take out a target from several kilometers away. With an arsenal of weapons at his command, Golgo 13 is hired by a variety of people to take down hijackers and more - but he also must protect himself against those who want to take down the legend himself!
both have heartless, emotionless main characters.
Who get what they want and know how to get it.
Both anime have sex in them.
Blue flames is more of a drama type anime, whislt Golgo is a bit more on thriller side.