The couple hung out at Sunset Hotel’s Tower Bar in West Hollywood in California last week.
“They were super low-key and having a good time. They were really sweet with each other,” a source told people.com.
Following her split with singer John Mayer a year ago, the 31-year-old has been with Bloom since early this year.
Last month, they were were seen holding hands at Cindy Sherman’s self-portrait exhibition, “Imitation of Life”, at the Broad Museum here.
“They did keep an eye on each other still while admiring the collection from separate ends of the gallery. They had a very flirty energy,” said an onlooker.