2 Ideas 1 of which will likely be said no to and a second kinda 2 suggestions in itself. I was thinking as the first idea maybe a sexual preference system, you could choose between prefering female, male or herms which depending on your choice might say if you had male as sexual preference, lessen lust damage (or whatever its called) towards you from females and herms but increase lust damage from males and also boost your lust damage towards them as your char puts more effort into it as they like males. or you could select no preference and play the game normally.
My second idea is a Kobold TF item and a sorta dungeon cave with a clan of kobolds that unlike some kobolds are really into death n destruction which people arent much of a fan of. here you could kill/sexually subdue (dont know what to call winning through lust attacks) kobolds and have a chance of collecting a Kobold TF item that transforms you into a semi Kobold or full on if you get many and combine em with the body part reagents through alchemy, at the end of the cave you could also fight the clan leader who at the end you could either kill, capture or join with capture and kill making the cave pretty much lifeless but capturing lets you bring the leader to the town for a trial, or if you join him you get to sex him after he enchants his dick and then while you are fucking him you progressively begin to transform into a full on Kobold, if sexual preferences were added I thought that the transformation could also link to the sexual preference in which depending on your preference you also transform into your prefered gender if you arent that gender already, you would also be given the choice of changing your preference, that or you would be given the choice of 3 roles before you fuck him each relating to one of the genders which upon choosing would then proceed to you fucking him and transforming into a kobold and the roles fitting gender, after the transformation and sex you would then be given gear for the role and a key item in the form of a concealed talisman to identify your clan incase you bumb into a fellow clan member on your journey, the cave would then become a hub of sorts with an inn, a food stall and a personal room for you to sleep in. your companions would also swear to keep everything that happened a secret as to not make everyone else kill you on sight.
sorry if this was a mess and a horrible idea its just something that popped into my mind and I thought I would share it just incase, sorry for anyone reading through all of this XD