Many people ship Saji x Sona, that's why it is kind of risky for me to add Issei x Sona, even though from my point of view it is very likely Sona will actually become canon while there's no chance for Tsubaki to ever lose interest in Kiba.
Either way, Sona would be very late in game if that happened.
My focus is covering the canon harem (+ Raynare), I start games with the intent of completing them, and DxD so far is my biggest undertaking (with 25 volumes to cover), so I have no doubts I'll have to cut some stuff (even things I might enjoy or agree with) to make sure the game will actually be completed.
Still, I am fairly confident that given enough time, I'll be able to make most people happy as I'll be making some side games to cover the missing heroines.
I do not know what "femcel" means, but the only changes I've made are to Issei and custom content for Raynare since her character is pretty lacking for obvious reasons, the other characters will be as close as possible to the source (or at least my understanding of it).
Yeah, unfortunately that's my weakpoint
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I am really vanilla and do not understand most fetishes, whereas other fetishes I find to be pretty gross.
I'll try different things for sure though, given that there are so many volumes to cover and some heroines (such as Rias) happen relatively at the beginning, it would be pretty boring for everyone involved if she had the same/similar scenes.