While he warmed up , Sheldon 's thoughts turned to Monica , the woman he had met while she had been under investigation for murder . The evidence eventually pointed out the real killer , but Sheldon 's involvement with her had drawn some fire from his teammates , especially Mac . Mac had been firmly against Sheldon 's relationship with Monica , particularly since she had been a suspect in a murder investigation .
The disappointment had been all over his face when Sheldon came clean about his relationship , making Sheldon feel like a child being shamed by his parents .
Emotion: Disgust