Basic tomato coulis

Remove the stems from the cherry tomatoes, make a shallow cross-shaped cut in them, and blanch them in hot water

Cut the peeled tomatoes in half horizontally and carefully remove the seeds with the tip of a knife

Place the seeded tomatoes in a blender and blend until smooth

Pour into a fine-mesh colander lined with cheesecloth and leave in the refrigerator for half a day to overnight until done

[Reference]
Just leaving it for a few hours will release this much excess water. (If you leave it for half a day, three cherry tomatoes will release about 80cc of water.) This water is clear, but it has a rich tomato flavor, so it can be used in a variety of dishes, such as mixing it with egg mixture to make tomato chawanmushi, or adding gelatin to make tomato jelly. (*The photo shows a different recipe, "Raw Sea Urchin and Tomato Jelly" which uses water from tomato coulis.)