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- Insert Heart image again.
- Play with levels settings and make heart very dark, but with a few white spots.
- Place this layer above liquid image, apply Screen Blending Mode effect.
- Load selection for heart, contract it with 10 px.
- Create a new layer, fill selected area in a new layer with any color, Fill=0%.
- Go to Layer Style effects.
- Apply Inner Shadow effect, just like in the example below.