PEOPLE have been scratching their heads over Rihanna’s musical collaboration with Chris Brown, but she says it "made sense” and it’s "innocent.”Brown appears on a remix of her song "Birthday Cake” and she appears on a remix of his "Turn up the Music.” Their music union is noteworthy because Brown beat up Rihanna three years ago and is still on probation for the assault.She says the partnership allowed fans to come together, adding: "There shouldn’t be a divide. ... It’s music, and it’s innocent.”She called into Ryan Seacrest’s LA radio show on Thursday to explain her decision to team up with Chris.She said: "I reached out to him about doing ‘Birthday Cake’ because that’s the only person that really... it made sense to do the record."Just as a musician — despite everything else — that was going to be the person.”And the rumour mill is already swirling with gossip the pair are planning a romantic reunion as well. Over the weekend Rihanna tweeted the lyrics to a Beres Hammond song, in an apparent hint to fans.The post read: "When they see me with you, I wonder what the crowd would say? When they find us together, what will all the people say?”