Jennifer Lopez's boyfriend Casper Smart says it wasn't love at first sight for the couple

However, Casper - who, at 25, is 17 years younger than his superstar girlfriend - insists there were no romantic sparks between the two of them initially.

When asked by ABC News correspondent Amy Robach if it was love at first sight when the pair met, Casper said: "I don't think it was, for either of us. It was just very natural, you know, natural how it happened.

"There was nothing before, no flirting, no nothing."

Jennifer, 42, accepts the relationship will attract a lot of attention and that the pressure on her partner can be intense.

The 'I Need To Know' singer - who has four-year-old twins, Max and Emme, with Marc - said: "It can be difficult for anybody who has to stand by my side ... But at the end of the day, I know that I deserve that (to have love)."

Jennifer is currently on tour with Enrique Iglesias - who appears with her for the 'Nightline' interview - and Casper is the head choreographer for the concerts but Jennifer insists it isn't tough to work with her lover.

However, she admits it has been difficult when she has worked with some of her previous partners - who include P. Diddy and Ben Affleck.

Speaking about working with her lovers, she said: "I've done it many times and it's difficult with some people and with some people it's easy. It just depends on the personality of the person."

Casper insists Jennifer is good at taking direction from him, but ultimately "she's the boss".