First of all, thank you for leaving a comment! Secondly, as far as I'm concerned, almost any race in the DnD universe is compatible - there's no lore on whose genes are compatible with whose. Nor there is any lore on whose genes are dominant. My first playthrough was Tav Dragonborn with Karlach and I am sure they managed to conceive and then raise their children after the Epilogue :)
It would have been ideal if Tav had asked Karlach about tiefling anatomy right away. Can they even have children with humans?
First of all, thank you for leaving a comment!
Secondly, as far as I'm concerned, almost any race in the DnD universe is compatible - there's no lore on whose genes are compatible with whose. Nor there is any lore on whose genes are dominant. My first playthrough was Tav Dragonborn with Karlach and I am sure they managed to conceive and then raise their children after the Epilogue :)