I love being naked, Spice Girl says
She added to Britain's Daily Star newspaper: "Stephen wanted to inspect the underwear before I signed up. He didn't want me involved with anything tacky but when we saw the range we fell in love with it.
"Stephen especially likes me in the bridal range. It's white, lacy and dainty. He says it makes me look innocent. I can't help thinking it would take more than a pair of white knickers to do that!"
Mel also revealed she was "shocked" to be offered the contract, following in the footsteps of previous Ultimo models like Girls Aloud beauty Sarah Harding and Rod Stewart's wife Penny Lancaster.
She said: "I was shocked. I mean, I'm a mother twice over. I'm in my 30s. I couldn't quite believe it when they said they wanted me parading about the place in sexy lingerie.
"I was dead flattered."