It is easy enough simply to describe the ISFP as attracted to the beauty in things, whether they involve artistic animal expressions or live examples of natural products. It is more than an attraction, it seeks a primal attachment involving a sense of unity with the object being appreciated. The ISFP seeks out (sometimes by creating) that which invokes this sense of oneness expressed inwardly as a feeling-state.
Some might call this a natural high. And that's another reason for choosing the double rainbow guy video as an example, as he is obviously experiencing an altered or "higher" state of consciousness in a very authentic sense.