Oh, and did Satayoshi leave for the bathroom by any chance?
EDIT: Gosh, I'm having so much trouble with the dying message!
EDIT2: Oh yeah, one more question! How did the culprit enter the victim's room? Did the culprit have a copy of the key, or was the lock tampered with, or . . . ?
EDIT3: Summary of case for all you detectives out there . . .