Funnily enough, I'm giving this manga a 10/10 and I really don't know why. Honestly, the art isn't all that good, the story falls victim to copy-paste character referencing and lingers upon a perverted border of being misleading for readers.
However, before you're put off, I will say that the manga itself performs so well that the aforementioned problems are immediately overridden by a deluge of the raw emotions of a great story with a large space to fill the reader's sympathy with.
The story itself starts off shamelessly, and rather humorously, with the ever-so taboo subject matter of masturbation purely taking the center stage in the first volume, but quickly descends into a cesspool of raw feelings and human emotions conveyed by ridiculously realistic characters before tearing apart your heart and then piecing it back together. Plot twists also show unfathomable realism, such that the chances of predicting what happens next fall to record lows. The orgasmic climax of the manga fits it, without giving the reader too much despair. You will, however be left with feelings that will carry weight for a lifetime and find yourself thinking about the manga for a good week or so.
However, one could say that the characters fall victim to stereotypes and schemers of the human mind, but after great character development coupled with their ever-so-unique personality attributes, the depths of their inner psyches are such that they can be described as nothing but realistic.
The art itself is rather unprofessional, mainly because it is. But despite its lack of prowess, one can confidently say that it does its job. Characters are immensely expressive, very recognizable and have suiting visuals to their personality, while the backgrounds are almost non-existent. The sketchy style suits the sour premise of the manga, but can be a little unbearable for readers used to higher quality.
Now that the outrageous rating has been ambiguously justified, I can personally say that it is the greatest manga I've read so far without a gram of exaggeration. An instant favourite of literature. A showcase of humanity's prowess.
If you haven't read it, stop whatever you are doing, throw away shame and shyness and start reading the first chapter wherever you may be. It's really that good.