Oops! Demi Lovato Nip Slip In Concert -- Photos

Demi Lovato has a nipple peak during a concert in Dallas. Demi Lovato leaned over in a tight-fitting dress during her concert in Dallas.Demi Lovato tweeted: 'Woke up so sick this morning but I WILL NOT let it stop me from putting on a killer show in my hometown tonight!!! Come on Dallas TX!!!!'