At the time of this review I have only read the first 18 chapters as this manga is on-going.
Happy Sugar Life is excellent. If you don't know anything about it, I'd say its one of those mangas where you should probably go into it without knowing anything, similar to GakkouGurashi and of the like. Just know it isn't for the faint of heart.
The story is based mostly on the mindset of the characters. Looking seemingly innocent at first, all of the cast(of the very few there is) has at least something screwed up about them. The 2 MCs are of an popular girl and her
"lover" of whom she is willing to do anything to protect. In fact she's trying to protect her "happy sugar life"(lol).
Like I explained earlier, all characters have something about them. They also all have differnent ways of how they interpret love or ideas about life. I do think that pedophiles are the absolute scum of society, but the way the mangaka shows how the lolicons and how their mindsets affect their descions was really interesting.
I despise "moe" kind of artwork but the art hepls in the case of the manga as well. Using that same art style really showed the shift in tone for certain moments and really made some dramatic moments all the better.
Really Happy Sugar Life is not that happy, its horrifying if anything(kinda spoiler, mc is a yandere. See how well that goes :P). And yet its addicting, even though I know it won't have a good ending. I've enjoyed it thus far and can safely reccomend it. As safe as it gets that is.