After hearing and reading a lot about SubaHibi, I'm rather disconcerted that it both ends up rather high here, and also that there are quite some VNs below it...
...but Higurashi and MLA on the same level feels a bit silly, not to mention putting Rance, a rather vanilla eroge of all things, below all of the aforementioned. Saya no Uta is also kinda tame compared to MLA and (I think) SubaHibi, to a lesser degree I'd also say the same for Euphoria. Also... Fate is more messed up than Zero Escape and Danganronpa, what??
So yeah I'd put MLA for just the chomp scene alone (I've never seen anything quite that fucked up and scarring in fiction) and SubaHibi (even though I haven't played it yet, just based on reputation) at the bottom.