Its edgy, but it has a reason to be edgy.(this and the last line are the only important points here)
It is a story about a lot of things, as any good story should be; and never gets stagnated always keeping a good rithm. Needless to say, no moment is wasted as everything has a point either thematically narratively, to be funny or a combination or both.
Worderful management of scenes, delivering huge narrative and emotional (fire) punches.
Its not meant for everyone.
Im literally a fanboy of this manga, as you can see by the 10 i gave it, but I really have thought about the quality of it, and even re read it and i stand by my words, its not for everyone, but maybe it is for you.
But all I have said doesn't really matters, its just a byproduct of how honest the story is and how much the author cares about it.