Her character Lauren Branning shares a kiss with her cousin Joey during tonight's visit to Albert Square, a storyline that was confirmed in September.
The Walford actress insisted that, while the character of Joey is attractive, the Inside Soap Awards' 'Sexiest Male' himself "isn't sexy".
Jossa, who is dating fellow cast member Tony Discipline (Tyler Moon), told The Sun of Joey: "It's that smouldering look he does.
"His best look is when he's got no top on. Or when he wears a T-shirt, with his ripped-ness coming through. But that's Joey - David Witts isn't sexy."
However, Witts agreed with Jossa's evaluation, adding: "I'm a bit camp, slightly posh and I sing a lot. I'm different from Joey in almost every way imaginable.
"I've never been a player. And I'm punching majorly above my weight with my girlfriend."
Of the kissing scene itself, Witts confessed: "I went bright red when we rehearsed it. It's Lauren kissing Joey, not Jacqueline kissing David."
Meanwhile, Jossa recalled: "I didn't blush - but David was like: 'Can we do another one please?' It doesn't feel like a real kiss because you've got four cameras pointing at you.
Claiming that she would "never" be attracted to Witts, Jossa added: "It's not something we go home and discuss with our partners. It's irrelevant."
> EastEnders star David Witts: 'I'm not Sexiest Male'
> EastEnders David Witts: 'Joey's crush on Lauren was obvious'
> EastEnders David Witts surprised by fan attention