The Jewel and the Comet

Glenn is a normal graduate student (aside from his kinks and genderfluidity), living a normal life with his normal girlfriend, Vivy (a spy for an interdimensional agency with her own kinks). When Vivy is called away on a scouting trip to stop a rogue comet, Glenn finds himself pulled from his normal life into an adventure of his own, navigating the multiverse with only a snarky starship as his guide.