If read carefully I said routes,characters, story are changed
Hey friend, just wanted to be nice about it, but as others had alluded to, perhaps now (or ever for that matter) is not exactly the right time to pursue this remake project of yours. There are a lot of roadblocks that are actually quite detrimental to the overall health/direction of your project.
A.) Permission from the original character to remake their work.
B.) You run the risk of detracting from the original work with your remake by rehashing the game where there really isn't a need for that as the game is already quite stellar in its original/vanilla state.
C.) I would suggest making your own version of an NTR game that is holistically quite unique in its own right. I.e., nothing that overtly ties back to the 'Scars of Summer' title. Being original while showcasing your own talent and crafting your own NTR experience is part and parcel of what makes your creative vision in the (already saturated) NTR market that much more memorable and distinct from a competitive differentiation standpoint.
D.) Also, Scars of Summer After Release is presumably on the horizon as well. So the induction of your remake project could not have arrived at a more untimely manner.
Lastly, to me, it is still a little questionable as to whether it is even sanctioned for approval by the original dev of SoS or not.
You might just be better off crafting your own unique version of an NTR game and not using SoS as the baseline for your remake project.
I feel that it is not going to be a very fruitful project, to say the least. I just wanted to be nice about it and give you my $0.02 for what it is worth.