I saw this on the Twilight spot.

This is how it goes..

Person A: Serverus Snape.
Person B: Bella Swan
Person C: Serlla Swap.


The first two people say the parents, then the thirst mashes the names together to get the baby name.
they dont have to be crossover, adn they can be of the same sex.

Ill go first;

Rosalie Hale.