>>106193656No.
Brad and Jenny don't have that kind of relationship.
Jenny doesn't have that kind of relationship with anyone on the show. However, she is unusually protective and territorial when it comes to Brad and his romantic interests. Is she jealous? Afraid of losing her best friend, or something more...?
Alas, we may never know.
The only thing we do know for absolute certain is that it'll never ever ever happen for Sheldon.
Not ever.