I actually like Entrails of a Virgin (and its sequel Entrails of a Beautiful Woman)
Yeah it's silly in so many ways, but I found the silliness did add to the overall bizarreness of the film and the entertainment value.
The films are curios for sure, and don't really provide you with much rewatch value... however, if it's Japanese sex and violence shifted towards the odd end of the spectrum that you are after, then I can't recommend these films enough.