For those who think burgers are the (fast) food of love, then they are all set for a romantic evening: branches of Burger King in Israel will sell an "Adult's Meal" for Valentine's Day, including an adult toy, starting in the evening.

In a 30-second commercial for the meal, posted on YouTube by ad agency Leo Burnett Israel, a voiceover says: "Kid's meal? That's for kids," as the music changes from chirpy to something more seductive. "Burger King presents the Adult's Meal, with an adult toy inside. Only on Valentine's Day, and only from 6 p.m.," the ad continues.

The ad, which also appears on Burger King Israel's Facebook page, has been watched more than 150,000 times. The adult toys pictured include an eye mask, mini feather duster and head massager, next to an Adult's Meal box design featuring a neon hamburger and an 18+ sign. CNBC.com contacted Burger King Israel but no one was available to comment.

A TV ad still from sex toy retailer Lovehoney

In the U.K. meanwhile, adult goods are set to see an increase in sales online around Valentine's Day, according to new figures from performance marketing company Webgains. The "Fifty Shades of Grey" franchise has caused an increase in online sales of bondage products, according to an emailed report. Webgains predicts a 50 percent increase in online sales of such goods around the Valentine's release of Fifty Shades Darker, which premiered in London on Thursday. Sex shop Ann Summers saw a 43 percent increase in sales of bondage products online between 2015 and 2016, using the Webgains affiliate network, and the report claims other adult retailers including Lovehoney and Bondara are also likely to see a surge in popularity.

A Snickers billboard at London's Waterloo station Jeff Moore | Snickers

Other brands have focused on different aspects of the feast of St. Valentine, and have given away products. Snickers has replaced its strapline: "You're not you when you're hungry," with "You're forgetful when you're hungry," attaching free Valentine's cards to billboards at London's Waterloo station. It will also give away 3,000 cards on Wednesday for those who forgot Valentine's Day. And sandwich chain Subway is giving away a free 6-inch sub to customers who buy a large drink, as part of its "Customer Appreciation Day" in the U.K. Meanwhile, the U.K.'s National Health Service is running a Valentine's Day campaign to encourage people to give away a kidney – while they are living.

Comedian Alex Smith performs in an ad encouraging living kidney donation