Who is Loudon Reily from The Last of the Menu Girls and what is their importance?

Loudon is a graduate student, working on his thesis, when he and Rocio meet and become a couple. This is not a lasting relationship; first, because Rocio is continually developing crushes on his friends; and second, because he shows himself to be a rather self-absorbed individual. When Rocio becomes ill, Loudon sees her condition as rather an inconvenience to himself, as he focuses on his thesis. Once Rocio graduates, Loudon is no longer in her life.