That's an interesting idea & I do enjoy the idea of cock blocking Hunter on a 3rd daughter. Also, I've noticed a lot of talk about time travel can I get more context on that?Honestly the story would just be far more interesting if it turns out to be Hunter. Drew may or may not even show up in the story again but for most part the dynamics that would come from Lucia finding out the old bastard is not only her father but also how she would react to it could be a sight to see.
Besides lets be honest - her full on embracing of her kinky sexually driven side after supressing it for so long does seem to indicate she is a chip off the old block, certainly far more than Drew ever was (much to Hunters open disappointment till her mother came along and caught his eye). Finding out he is her father might spur her to connect more with him which would be the opening Hunter has been flat out deprived of so far to try and get in her knickers as shes smelled a rat with him since minute one.
Also would love some sort of interaction between Eva & Lucia if not an outright threesome.