Big Sean is "still grieving and in shock" following the death of his ex-fiancé Naya Rivera.The 32-year-old "Bounce Back" rapper took to social media late Friday (July 17) to share a moving tribute to Rivera, who recently died from an accidental drowning in Southern California."Rest In Peace Naya, God Bless your Soul! Thank you for blessing us all with your talent and presence," Sean captioned photos of Rivera on Instagram.