Wow man.... Your dialog/comedy is really phenomenal! If it isn't among the best of its kind I've seen, its up there. Your models are hot (aside from grandpa). Your build up even with the extreme comedic situation is excellent. So obviously, I'm hoping on the paetron train.
That said the hopefully constructive criticism that I'm sure you've heard said before, but I'm going to say it my way anyway
![Stick out tongue :p :p](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
. While I am not a fan of NTR, I can understand its place, and too degree appeal. I also think most of us here that are even part of the "NEVER NTR" train, can accept it when presented like you have it with a toggle.
While I did find some of grandpa's antics humorous (I find his dialog when actually "teaching" the MC best), I think you would benefit monetarily and story wise from making him the father's dad (as far as the incest patch goes to make his attempts at wooing more believeable and him potentially younger) and give him a less repulsive model. It would cater to the NTR people and make the scenes you do with him more worthwhile I think in the long run if your going to actually go as far as you did with Eva. (The dialog was hilarious, but it was hard to keep up with during the train-wreck of visuals lol). I don't wanna knock your vision, but it just seems like a lot of animation work for something most can't fap too. lol
On that note your animations are alright but could be better (I assume your doing them yourself?), but if you can make this take off you might wanna get a semi-pro to hop on unless you really wanna do it yourself for the learning. I also greatly approve of the helperbot, but even with it some of the gameplay gets a bit grindy. Anyway, look forward to seeing more!