Ryuu no Hanawazurai

Teenage Shakuya, the next head of the Dragon Clan, suddenly finds herself with two fiancés! The first vanished years ago but has now mysteriously returned. But betrothed number two is not about to just step aside. What's a girl to do? Her mother decides that at the end of a year, Shakuya will marry the man she has the strongest feelings for. How that will be determined is by "magic tattoos" on both of Shakuya's hands, each representing one of her suitors. As her love grows, so do the tattoos! And complicating all of this is that fact that whenever Shakuya gets upset, she turns into a fearsome dragon!