The center of the Milky Way hosts a supermassive black hole, a cluster of young, massive stars and various gas features. Recently, two unusual objects have been found orbiting close to the black hole. These have generated a lot of attentions because they appear to be tidally interacting with the black hole and they might increase its activity. However, no consensus has been reached about their nature: they appear as gas and dust clouds but also display the dynamical properties of stellar-mass objects. Using 13 years of data obtained in the near-infrared by the Keck Observatory, we discovered several additional objects with these same characteristics, all orbiting very close to the black hole (within 0.04 parsecs). These objects form a class that is probably unique to this environment and they require a common formation mechanism. I will present the observations of these objects, the formation scenarios and their implications for our knowledge of this extreme region.