_____DAENERYS KNEELS____
Daenerys is planning to invade Westeros with her army, She need to cross the narrow sea first, for that She needs 400 ships.But She didn't have any ships.
Only king of Slavers Bay has the Navel fleet in Essos, but he is affiliated with Lannisters. He wouldn't let a tyrannical Targaryen queen to cross the sea and invade Westeros unless there is huge benefit for him in that. Daenerys can't go to war with slavers bay king, if she did she'll lose both Army and Ships.
So she has to Convince the king that alliance with her will be more profitable than alliance with Lannisters.
She invites King for Dinner.
When king enters the room, she orders all the servents to leave the room. King is little bit worried cause Alone in the room with a power hungry targaryen isn't a good Idea. they both discuss about the possible outcomes of the war.
Daenerys offers a lot of Money and promises him massive Lands in Westeros,but the king isn't satisfied by the Offer. So Daenerys uses her Ultimate move to satisfy the king.