Dobriga its a portuguese word that derives from the word "obrigação". It´s translation meas "from obligation" or in portuguese "De Obrigação". It´s used to confirm something that someone asked you or in the beginning of a sentence to reinforce that you are going to do some task. Its has a some variations, such as "Dorbiga", "De Obrigations", "Dobrigations" and "Dorbigations".
*When used to cofirm something some one asked you*
Person1: Olha, podes me ir buscar um café?
Person2: Dobriga.
*To reinforce something that you are going to do*
Person1: Dobrigations, quando chegar a casa vou dormir.