Luke Sullieman
From Tardis Wiki, the free Doctor Who reference
Luke Sullieman was a Therian student of River Song who became a good ally of hers while she taught on Cheska Major. He accompanied River on at least two adventures: one with the Decayed Master in Cheska Minor (AUDIO: Animal Instinct) and one with Weeping Angels in New York City, during the 1930s (AUDIO: Carnival of Angels)