It took me more than a little time to work up a love for this manga, and had I not been in a situation that left me with a lot of time on my hands and nothing else to do, I probably would have dropped it after the first chapter.
With that said, this is a really wonderful manga. Erotic, cringe-worthy, poingant, and occasionally even funny. The story leaves more questions unanswered than I would like and the art took some getting used to. The "humor" had a tendency to interrupt some of the most emotional moments in a way that was off-putting. But I don't know that I have ever read a manga that used sexual deviance as a vehicle for understanding interpersonal relationships better (and it's a theme I love to revisit). The journey that the two main characters take has all the messiness and ambiguity of reality and that's what makes this manga so compelling. Love, uncertainty, envy, and loss are played out on a stage that is farcically eroticized and provides a more comfortable conduit into laying bare the parts of human relationships that we'd rather not look at too closely.
I highly recommend this manga, altough perhaps you should avoid reading it on public transit or near playgrounds.