Boy Meets Girl is an ITV comedy-drama television miniseries starring Rachael Stirling and Martin Freeman. In the show, Danny Reed (Freeman) is struck by lightning. When he wakes up from the attack, he is inside the body of a woman, fashion journalist Veronica Burton (Stirling). Written by David Allison, the series began on 1 May 2009.
Danny Reed and Veronica Burton share the body of Veronica Burton in the show.  
There's no mention of the dynamic between the characters in the statement. It only says that Danny Reed wakes up inside of Veronica Burton. There's no way to tell if he's replaced her in her body, if she's in his body, or if they are sharing her body.  Not without additional information.