Car maker Jaguar has been criticised by the advertising watchdog for running a mail campaign that may have made people think they were being stalked.
The campaign aimed to drum up interest in Jaguar's XKR model
The luxury car firm sent out anonymous letters which promised a "photograph next week" of a "perfect match".
Dozens of people complained to the Advertising Standards Authority (ASA) about the mailing on the basis that it suggested they were having an affair.
Jaguar has apologised and promised not to use the same approach in future.
The ASA upheld 37 separate complaints made to it about the "sexually suggestive" letters.
The watchdog said the mailings did not make clear they were marketing material.
It added that the "sexually suggestive" content of the letter "could put a strain on a recipient's relationship" or lead some people "to believe they were being stalked".
The correspondence arrived in an envelope with a stamp and what appeared to be a typed address.
Inside, the typed letter, dated 14 February, contained a string of cryptic messages.
It read: "Everyone has their weakness. So, what might drive you wild?
"Could it be the touch of skin on your fingertips? A long, honed body? Firm sensuous curves? A deep, responsive purr?
"Or, do you simply like the feeling of raw power?
"If so, I think I have the perfect match for you. I'll send you a photograph next week."
Meant as joke
Letters sent to women were signed "Ian Major", while those sent to men
ended with the name "Elizabeth Jones".
A follow-up mailing then arrived in a large black envelope with the words "prepare
to be seduced" printed on the outside.
Inside was a leaflet for the Coventry-based firm's XKR sports car.
Jaguar has apologised for the Valentine's Day themed campaign which it said was meant to be "humorous".