This unnamed angel was one of many encountered by Lucifer in 2016.
When Lucifer arrived in Heaven, he gathered a handful of angels, including this one, to hear him out. He mocked their effort in trying to defeat The Darkness with their combined smite, which failed. He explained that the lesson they learned was that the angels needed him for help.
All the angels went quiet, until one spoke up and accused Lucifer of murdering Jofiel. Lucifer brushed off the accusation by suggesting that Jofiel had exploded himself. When another angel reminded Lucifer that God had cast him out, Lucifer explained that God's reason was Lucifer didn't accept God's obsessive love for mankind.
The first angel countered that mankind was God's creation, a statement which drove Lucifer to list all the sins committed by humans, from the Salem Witch Trials to the Third Reich. The second angel responded by saying God called Lucifer evil, to which the first angel agreed.
Lucifer ignored them, and explained God's negative stories about him were intended to glorify God. This angel then asked what Lucifer was offering them, and Lucifer told her he was offering a means to defeat The Darkness, much to her surprise. She asked if Lucifer was planning to reason with their aunt, and Lucifer admitted doing so would be futile. Instead, he would help lock The Darkness away as he had done with God many years ago.
Convinced to work for Lucifer, this angel and the others began walking out the room. However, The Darkness sent a shockwave towards Heaven, forcing all the angels to rush back into the room where they were knocked off their feet by the force of The Darkness' attack.
Once things calmed down, Lucifer used the incident as proof that the angels really did need his help.