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| | Like what Wispa said, you can add shadows on the clothing and some light. | Also I noticed you're using GIMP, so I guess the multiply can be found there.
 | As for the lighting, I am not sure but I guess you can make-do by air-brushing in the side of the light source and lower opacity.
 | You can also consider duplicating the outfit, change its hue and saturation up a bit and lower the opacity to make it coherent with Tink. If you just want to change Tink's body, change the hue.
 
 | Hope this helps hng I am kinda bad at explaining things lol
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