Laroq was a Phoenix colonist who met the Fifth Doctor, Erimem and Peri. Like all colonists there, he lived in a state of profound isolation, almost never leaving his room. He was romantically attracted to Bellip, but didn't possess the social skills to get her to leave her room and interact with him in person.
He met Erimem first, who spent a good deal of time trying to understand his unusual social isolation. When later he met Peri, she was furious with him for losing Erimem.
Of the three colonists encountered by the TARDIS crew, he fell between his friend Vidler's desire to crush the colony's system of enforced social isolation and Bellip's extreme agoraphobia. (AUDIO: Three's a Crowd)