It's better if you lie to them, the dominant one tries to shank you.
Dunno what happens if you mix it up.
From a porno game logic standpoint I think you're supposed to tell them the truth (the answer is always listen to your dick, also Dad is usually the villain), but your dad is chill and even gives you an easy little summer job so screwing him over is dick move.
I mean seriously, you meet her for the first time and she goes "I'll cocktease you a bit in the future if you screw over your family." Lady, I'm boning like 6 different hot chicks already, you can take a hike.