Similar to a mini break where you take your partner away somewhere nice; a mani-break is where you substitute your partner for your mate Gary and somewhere nice for a cheap air BnB on Exmoor, a boot full of booze and reruns of Match of the Day in order to get out of the house.
"48 cans of Kestrel and a copy of Cool Runnings on DVD, that'll be £28.99, enjoy your mani-break."