kinship; likeness; closeness
The only good reason for marrying is a deep personal affinity between yourself and your chosen spouse.
ad (to)#finis (end) (Latin)
affinity: a+feel+near+ity - you always have a feeling of kinship (affinity) for people you are affiliated with. AFFINITY sounds like AFFEEM in Hindi which is a drug. So druggists have special kinship or affinity for affeem. Mathematicians have an affinity for infinity.