Ramona Nowitzki is a graduate student at Caltech who is a huge fan of Sheldon's work and apparently has a near-obsessive crush on him. She only appears in "The Cooper-Nowitzki Theorem". She meets Sheldon personally in the cafeteria and arranges to have dinner with him in his apartment. Where other people might be worried about such behavior being reminiscent of stalking, Sheldon reacts positively to Ramona by appreciating the fact that he's getting a free dinner. During their date, the rest of the gang is sitting on the couch as spectators of this strange turn of events.