Adding another old man to Regulus's roster, I think Regulus and Corvus Lestrange VI (my name for the father of Rabastan and Rodolphus) would be so deliciously filthy, Corvus treats Regulus like and absolute doll, buys him anything he even looks at twice, like he's so sweet on him up until they get to bed, I think with Rabastan and others his age (or only 10-15 yrs older) Regulus is on the more dominant-ish side, definitely really bratty, but when it comes to Corvus and the other way older men Regulus is such a compliant princess (with just a fraction of brat cause he can't help but be a tease), and also Regulus is fucking both Rabastan and Corvus but while Corvus knows about Rabastan and even loves the idea of fucking Regulus better than his son does, Rabastan would die if he knew about Regulus and his dad, he'd be so possessive over Regulus, so jealous and insecure seeing him with other men even though Regulus would have a soft spot for Rabastan more than he does with the others. Pandora knows Regulus is fucking her father and her brother but won't tell him anything because she's the type to let it all run it's course, she also knows if she tries to help Regulus he'll just close himself off because Regulus always feels like he knows what he's doing