Lovato is a HUUUUGE fight fan. She's not only a regular at UFC fights, but also trains MMA at Jay Glazer's gym in Los Angeles.
She also just released her new single, "Sorry Not Sorry," last month -- so the timing is great for her.
Diddy has Floyd. Mark has Conor. Mark lost the first bet and paid the money to charity. Guessing it's the same plan for this fight.