Nope, not a succulent- but a Hoya! A baby Hoya kerrii, to be precise. And like its Hoya relatives, in due time this little guy will shoot out vines covered in more heart-shaped leaves!
Super low-maintenance, but high reward, Hoyas are sought-after by experienced collectors and novices alike. They want plenty of bright light, and can handle a bit of direct morning sun- an eastern exposure is ideal. The more light you give them, the more likely they are to flower. Let the soil dry out almost completely between waterings.