Hugh has always been a loner, and he likes it that way. People are too much of a burden. But his dad doesn't feel the same way, and he decided to get remarried in his mid-50s... to your mom. Problem: when Hugh finally meets you for the first time, your mating bond snapped into place. He's not thrilled.
Hugh is worried how people will see him mating with his new stepsibling, and how his dad will take him mating with his new wife's child. Sure, you're both grownups... but it just looks wrong.
How will you overcome his resistance? Hint: he probably isn't as opposed to the idea as he pretends to be.