Um. Wow.
I rate this 9/10.
It is an intelligently done manga, with memorable events, lots of pop-culture references, and plenty of trope subversion.
The main character has an iconic look, a strong sense of ethics, and a unique personality.
The manga is also extremely silly and very horny, and the pop culture it references is mostly porn, but the good points remain.
It's probably even better if you can read japanese, what with all the puns.
To give a better score, I'd like a more cohesive plot, more consistent metaphysics, and more strategy from the MC about getting new skills and abilities. I'd also like the love interests to have more fleshed-out personalities.
But, well, doing that would probably detract from the humour...