It doesn't sound like an attempt to further a relationship, as for "*Bronc Rider Sex" so the answer must be

that the question had to be asked and
the questionhad to be answered
so that there'd be a reason for a murder.

If there wasn't a murder, it wouldn't be a folk song.



*Bronc Rider Sex as explained by an old cowboy:

"You get on doggie style and grab her by her breasts.

"Then you say

"         'I think your sister's are a bit bigger'
*
*
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"--- and then you try to stay on for 8 seconds."

John