Here several options of liquids falling into glass.
I threw it from the hand because I think that's when it becomes the most surprising.
So the setup is small, the glass and me.
I assume that you are going to be even closer.
4 and 4A are milk and coffee mixing.
The rest speaks for itself.
1: Black coffee 20 ml 500 frames
2: Creme coffee 20 ml 500 frames
3: milk 500 20 ml frames
4: Milk and coffee 10+10 ml 1000 frames
4A: Milk and coffee 10+10 ml 1000 frames