The biggest flaws here are change of tenses and passive voice. You normally have present tense in the review, so the past tense in your first line and Overall section are jarring.
Just a few lines that I think could be changed to active voice for the better:
the true guro nature of this bizarre masterpiece is revealed <--- also, did you mean 'gory nature'?
there is graphic depiction of rape, violence <--- could be 'Midori depicts rape, violence...'
Midori is portrayed as a weak and helpless character <--- why not just 'Midori is weak and helpless'?
OTHER MINOR ISSUES:
devastation of Midori within the freak show will have a varied reaction depending on the tolerance to cruelty by the viewer <--- did you mean 'will have an effect'? Also 'depending on the level of tolerance of the viewer' OR 'depending on the tolerance level of the viewer' OR THE LONG VERSION 'depending on how tolerant the viewer is to cruelty'. Nobody is ever tolerant 'by' something
Although musically simplistic, it is not memorable and does not suit the unusual artwork <--- 'musically simplistic' sounds odd since you're already describing music. Do you mean 'structurally simplistic' or 'simple in composition' or the like? Also that 'Although' isn't fitting since you're not offering an alternative view in the following clause. Maybe 'Because it's musically simplistic...' or 'As well as being musically simplistic...'?
The entire Sound section has that repetitive structure. Because of this, this happened. Considering this, this is the case. Doing this, my friend did that.
on one hand, he uses cruelty to keep Midori by his side <--- on THE one hand
and grants peculiar, but blissful visions to her <--- 'and grants her peculiar but blissful visions' NOTE: no comma
Unfortunately, much of the characterisation within the show leaves a bitter taste in the mouth due to the vicious and despicable treatment of Midori <--- could be smoothed out and have wordage cut as 'Unfortunately, the vicious and despicable treatment of Midori leaves a bitter taste in the mouth' OR MORE SPECIFICALLY 'the supporting cast's vicious and despicable treatment of Midori leaves a bitter taste in the mouth'
Regardless of stunning artwork, and fascinating characters <--- remove that comma in the middle
Change all instances of past tense in Overall section to present tense. Will read more consistent that way.
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