Definitely use rope to bind her tits so they swell and turn red.
Nipples get very sensitive.
Hands pulled above head and secured.
Legs spread and secured.
Vibrator applied to clit until she squirts.
I think you will be hard the entire time she is gone.
No telling how much he is going to use her for his pleasure.
Inspect her when she returns.
She will need some tender licks and kisses to soothe her used body.
Good times for all involved