
there is a book called The Science of Kissing ( wal potak newei scientific research ekak).
read it
Yes, there's even a scientific basis to kissing -- and to explaining why we kiss. In what's called a "psychobiosocial approach," researchers study how psychological and biological factors combine to explain why people or animals behave the way they do. The concept of kissing may be linked with the good feelings people inherently attach to feeding as infants. For very young children, nursing or suckling is not only a way to get food, but also a critical bonding time between parent and child. Infants rely on their lips, mouths and tongues to drink formula or breast milk, but perhaps equally important, the action represents security, affection and comfort for both parties. As you grow, you remember the pleasure of these early memories, leading to a strong subconscious association between the mouth and feelings of love and attachment
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