Just going to start with, would personally label this "humanoid", not antrho. Since there's really nothing "antrho" about it. At most "neko" or whatever it's called. And in regards to the comment about "clopping", going with how the characters are loosely based references with the same name, not sure if it would apply well. But in either case, non-antrho versions of the actual ponies would not be "beastiality" either, as it indicates sex with a non-sentient creature. Which they are not. Just small pointer, but anyhow.
Did a larger review, (which might be quite a bit rambly) that I'll post on this's page on that "e" site in a few days, it's been posted there too. (doubt you'll go there, but eh, didn't wana wall of text this place) Anyhow, shorter version for here: (and rating it for overall "game quality", if I'd rate it for just the specific audience and purpose it has as bland generic porn, then the score would be around 3-4.) For the concept overall, saw nothing interesting or innovative in it, classic "slut and dick" pairing... or whatever that is called, think there's a proper term for it when it comes to porn. Rather impressive amount of time spent at the text though, even though I'm quiet sure around 95 % just spams to "get past the crap and get to the action". Compared to the "slave to pleasure", which at least had a slightly interesting story, this scores about as much story wise as "I have a package here for Miss Huegh Tiits...". But yeah, character personality lacks almost any resemblance of just well... "character" or "personality". One is just there to pleasure a penis, and the other is just there to have a penis to be pleasured. Very hallow cardboard-cut outs. Only real "resemblance" to the character the "Fluttershy" is based of is color scheme, name and to a slight degree, the shyness. (though, you do mention that with the "loosely based", so you kinda got that covered hehe)
Design wise, it's a very peculiar design. Only problem I saw (which was quite big) was the fact that there seemed to be a dozen different styles in there. The female thing had a different design and shading than the penis wielder, which had different from the cum, which was different from the hair which was different from the environment... like, if you make a sprite game, decide how many pixels you will use, and use the same for EVERYTHING. Not 32 bit for on, 64 for another and one 8 bit. It got very messy to look at. To speak of which: Anatomy. Can say it would not hurt if you studied some. I know quite a few say it's not needed in porn, and that "porn HAS to be bad" since "that's how it's always been." But it would honestly not hurt to put a little more effort into that. The vulva had frankly a rather pathetic design, shape and size overall. Everything just leaning towards an axe wound. (Or the "white human juvenile girl", as is also very popular among porn) But yeah, overall, it would not hurt to look up how things work and are located. With that said, there was really amazing lighting effects in this.
As for sound, the looping music (which can bug and double loop at the same time) was about what I expected, generic cheesy porno music. It however lopped very well. (bar from when it glitched as said) Your "fap" sounds tend to be above average, which is rare to see in porn. And they stuck to that standard here. The noises she made however... personally have to say they were an earsore.
All and all, I'm impressed by the seeming amount of sheer detail put into this, and actually raised the score a ½ star due to just that after some pondering. All and all, it is a rather terrible game with all things accounted for, but if just narrowing it down to it's core purpose and function within a very specific group, it does exceptionally well. One just has to have all the right kinks and fit into the stereotype/norm. Like the main audience for "popcorn movies". Those are also "terrible", but they don't have to be "not good" due to it.They fill their purpose as good "bad movies". Dunno if that made sense but... anyhow, gl with the next.