I don't know if you break any "rule" but in my mind you break Roleplay and Gameplay
In a world which is harsh, corrupted and focused on slavery I can't see any link between incest and a carebear "daddy issue" and can't really see why a daughter have to be managed in an other way than any forced slave in the household and surely not by introducing any new usage of any trait, there are so many attributes and variables useable for this...
It's better to have no access to a feature than to create "fake access" breaking the immersion.
If someone want absolutly make a mod on the subject here are some ideas for example for a more adequate mechanic:
- If a daughter have an intelligence greater than 40 or a willpower greater than 30 or a prude/shy/.... trait, increment a penality for any sexual act with her (cumulative penality)
- If a daughter have an intelligence lesser than 20 or a willpower lesser than 10 or a perverted/nympho/... trait, decrement this penality (cumulative)
- If an incestuous act occures during the day most other girls of the household will get as anger a value equal to this penalty if they don't have a corruption greater than 40 or any other limits to define (can be their will or their religion for example...).
Here is a try to make this more "realistic" and integrated in the gameplay but seriously in such a work I don't see why the daughters would be used differently than aany other slave or convict, except for eventual legal issues or to avoid loosing some patreons.
It's a player choice to use such a feature or not and if some just want it without any roleplay consideration just make an option on/off.