Butt implants on a very skinny tall girl. Will it look unnatural no matter what I do? (Photo)

There are a number of considerations here. If you are a tall woman with a tall buttocks an oval shaped implant may be correct. If your a tall woman with an average height buttocks a round will be the choice. In any case, a well executed surgery with placement of the implant within the gluteus muscle (butt muscle) will provide good coverage to hide the implant edge and provide a natural result. The real aesthetic consideration here is your desire to have a heart shaped waist and buttocks. Your body is very lean and creating a heart shape for it is unlikely achievable due to the lack of fat around your hip area. Implants won't add volume to your hips. In any case, you will have a beautiful result with properly done implants.Best

...not a problem!  Buttock implants are made in a multitude of shapes and sizes to fit anyones body. As long as the patient is fitted with the appropriate shape and size implant AND it is placed under the gluteus maximus muscle, the result will be as tasteful as properly done breast implants. Glad to help. 

Buttock implant placed intra muscularly would be the best placement for your body type. This will ensure the edges of the implants are hidden by the muscle.  I have many thin patients that are very happy with their results. 

Then most natural buttock implants are those that are placed in an intramuscular position. Such buttock implant placement does not allow large implants to be used but they will look the  most natural for sure.

If you do not have enough fat, then buttock implants are the way to go if you want augmentation.  Best of luck.