Time is measured in terms of successive events. If nothing ever
happens, there is no time.
Gravity, a fundamental force, relates to mass. Mass is made up of
atoms and atoms have sub atomic particles. An atom at absolute zero
temperature will have no motion, but there
will be motion of subatomic components and gravity has to exist for
that to happen.
If you are the only electron in the universe, yes you can attract any
other mass (if they may so come up) so you will still have gravity as
you have mass;
but as you are the only electron in the universe you will exist
without time.
Till some other mass comes near, to make up an event.
Hope this makes things clear.
Cheers,
Arindam Banerjee