It can involve affection as we work together in Christ, but affection is not a necessary element.
It involves coming together into a permanent bond of unity.
Also, in our culture, through "dating" people will often find a life partner and marry.
How men and women view a "date" and "dating" can have a profound effect on their future.
However, the Bible does describe three kinds of relationships with the opposite sex and gives certain characteristics of each relationship (there are others such as parent/child and sibling, but they don't clarify the issues of dating).
One kind of relationship the Bible describes is friendship.