A wedding ring. 8)
womb
The question should be 'what fastens two people but touches only one' The answer is a 'wedding ring'
A wedding ring
A wedding ring
A wedding ring
the heart
wedding ring
A wedding ring.
eom
wedding ring
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It would be called an "Ace". It also counts if only one person touches it, but some people argue that.
Maine touches only one other state, New Hampshire.