Eden ALWAYS had parts of lol sexual humor, from BEGINNING, with Eliah's parents.
Also, killing a drug dealer's prostitute lover, forcing him to kill himself on an airport runway is not gritty enough for you?
A prostitute/main character getting her ear cut off, her eye gouged out, and gangraped isn't gritty? Can you name 5 other manga where you would see that kind of thing? Even Caska just got a demon dick.
There's a some lols, but it has a serious undertone, with Eliah coming to grips with a relationship with a working prostitute.
And then immediately after that THEY FUCKING KILL HER.
There was nothing to be desired because it was fucking awesome.