Based on the principle of entrainment, the temporal developments of two heartbeats are compared under the influence of music. The degree of similarity in their rhythmic development then shapes and modulates a three-dimensional scan of the scene (also other environments were tested), realized as a sound-reactive point cloud in TouchDesigner. The conceptual framework for this is the concept of co-being coined by Martin Heidegger. This describes human existence as fundamentally relational and refers to the opening up of a shared world in which individuals do not exist in isolation, but are always anchored in a shared space of meaning and experience.