Halsey paid tribute to a lesbian couple recently attacked on a London bus by sporting a T-shirt bearing its photo during her concert in the city on Monday night (10Jun19).

The Without Me hitmaker performed an intimate gig at the Electric Ballroom, where she showed off a custom-made top with a picture of Melania Geyamont and her girlfriend Chris, who had been brutally beaten up by a group of young men on a London bus on 30 May (19).

Geyamont had originally posted the photo of their bloodied and battered faces on Facebook as she recalled the horrific homophobic attack.

On the back of the shirt, Halsey added, "F**k Your Straight Pride," referencing efforts by a group of men in Boston, Massachusetts to stage a Straight Pride Parade, a direct protest to the multiple events set up to recognise the LGBTQ community throughout Pride Month in June (19).

The singer used the opportunity to condemn the "vicious" beating and delivered a powerful speech about the need to protect LGBTQ rights all year round.

"When the glitter is being swept out of the streets, a lot of people get on those trains and on those buses, and they try to wash the rainbows off their bodies," she said, in video footage posted by fans online. "Because when Pride is over, it's not safe to be gay."

Halsey continued, "When people around the world ask the question, 'Why isn't there a straight pride parade?,' the answer is because if there was one, you wouldn't have to get on the bus and be terrified of getting f**king beaten or killed... Every f**king day on public transport is a straight pride parade."

She then urged her "queer" fans to "make a promise" to her, leading the crowd in a chant as she declared, "You need to promise me that you will not be afraid. Say it with me, 'I will not be afraid!'"

Halsey isn't the only celebrity to hit out at the Straight Pride Parade plans - Captain America star Chris Evans and rocker Mark Hoppus previously slammed the news, while Brad Pitt threatened legal action after organisers adopted him as their unofficial mascot. They subsequently removed his name and image from their website.