Donar by Bonnie Burrows

When Brianne Heatherton volunteered to support alien life conservation on a far away planet she really had no idea what to expect. The aliens that resided on that planet were sick and needed human intervention as soon as possible.
But it was on this journey that she met Donar.
A blonde haired, muscle bound weredragon who had an equally handsome twin brother named Conran.
It was clear that Donar wanted to enjoy Brianne all to himself and she wanted him too.
However, the dragon twins were used to sharing everything in life. And that included women…