...It is. Overwhelming, all-encompassing, and dangerous. I think it is like...looking at someone and understanding that despite being a fully realized individual, you were missing something until that moment. A feeling with no basis in logic or reason, similar to an irregularly firing synapse. A recursive impulse that brings you back to them again and again, because the thought of being without them causes the illusion of physical pain.

[he is incapable of explaining things through any other perspective than Science. who would ever have guessed this works.]

Think of it as compassion and trust taken to its furthest extreme. You care for them, desire nothing so much as their happiness, and are willing to place everything you are in their hands believing they will safeguard it.