Man this game is bad... Like... really bad...
I won't comment on the NTR itself or the scenes, but the game itself is terrible for a NTR game...
Why do I say that? Because there's no gameplay or character driven incentive to pair the girl with any of the guys that want to steal her away to the point of raping her in at least one case. The girl doesn't want to work with any of them and is on to all of their motives from the get go, and the MC being a weakling means that he needs to work with someone else anyway so it might as well be her since she wants to be with him anyway and doesn't like any of the other guys. The MC doesn't have any particular reason to push her to work with any of them. The other guys don't try to force the issue, and since each of them wants her for themselves, they don't work together in any way either.
On top of that, the gameplay itself doesn't really encourage pairing Aina with anyone in particular, especially since pairing MC with any of the resource gathering guys essentially nullifies their bonus except for the old-man. This means that the only effective pairs for the MC are Aina or the Old Man, and anything else is inefficient and requires a bunch of shuffling around to keep the right double bonus up. So in other words, you have the least pain in the ass by keeping Aina with the MC... which is really the opposite of what you want to be doing in a NTR game.
You want to make things so protecting the girl from the NTR makes the game harder or ensure that it takes more effort on the player part, or at least that there are character driven reasons for it or something.
This game has nothing, to the point where it could have been a VN with basic route choices, and nothing of value would have been lost...
Honestly, if all of this Dev's games are like this, he might need to rebrand into "Church of Lame", because he's failing at making the NTR particularly interesting.
Shame really, the girl is really hot, and I appreciate that there's actually interesting looking guys after her and not just completely hideous bastards... but if I just wanted hot art, I'd just look for CG galleries, and I play H-games because I want some measure of gameplay that makes sense for the game. This one misses out on that by a lot.