kuwash-anzi

.
 as
  if having exchanged places
  if not bodies ,
a curiosity began
  regarding the
  precise moment
  a kiss began ending
  and thus , more curiously yet
, had _ in just as
  asymmetrically-mirrored
  a manner
_ begun approaching
  so curious a
 beginning
.

Bodily requirements beg to differ amidst Replication, Celibacy, and|or Tantra. 

Most blatantly consisting of one trio, three duals, and three singles; simplistic examples including (1) a celibate lifestyle occasionally interrupted by tantric incursions into replicatory behavior (2) celibacy interrupted by replicatory necessities (3) replications arising via tantric lifestyles (4) non-reproductive cyclations between celibacy and tantra, or (5,6,7) each as a lifestyle unto itself. When ritualistic, likely not denoting passion - particularly sexual - though romance, filial devotion, belovedness, nuzzling and so forth are not necessarily devoid of same. Similarly sensibilities of sacrament or notions of universal peace. Of certitude some symbolic formalism or another via cultural tropes involving, in humans, 146 or so muscles. Of which a mere smidge larger than one-third of 100 are facial.

As for dopamine, endorphins, and oxytocin, the  mileage of each may vary, particularly when courtship feeding is considered le précurseur des baisers français.