Authorities say the shooting may have happened on Saturday. Police received a report of a gunshot in the area, but officers were not able to find anything when they went to investigate.
A friend who hadn't heard from the couple went to check on them and found them dead in bed at an apartment in the 500 block of St. Andrews Place at about 12:20 p.m. Monday, police said.
LAPD believes the man shot his girlfriend and the toy Pomeranian, and then shot himself. Investigators describe the couple as white in their late 30s or early 40s, possibly Eastern European immigrants. The building manager said they were both Romanian.
The names of the suspect and victim have not been released. A motive has not been determined.