After the battle in Dressrosa, Viola wants to thank Nico Robin from saving the country and protecting her niece.
« A Princess Gratitude »
Panel 1 - Nico Robin is in a room in Dressrosa getting ready to go to bed. She is standing next to her bed, getting off this dress : Image She has already pulled it down enough so her butt is just popping out, and she still has her thong and she is barefeet. She is looking at the door, where she just notices Viola in black and red lingerie (this style : Image ) and high heels. Voila is blushing and has a seductive face like this : Image
Panel 2 - Robin is kneeling on the bed and Viola is pulling her thong aside and munching her ass exactly like this : Image (Robin barefeet, Viola still with heels)
Panel 3 - They are both naked in bed. Robin grew a cock with her powers and she is fucking Viola doggystyle. Both are into it and Robin uses her powers to fondle Viola big tits with 2 hands coming from under her. If you want to get creative with her powers, be my guest