A man has been charged with murdering two Matalan workers who were stabbed close to the store where they worked, police said.
Andrew Patrick Saunders is accused of killing Zoe Morgan, 21 and Lee Simmons, 33, in Queen Street, Cardiff on Wednesday.
Saunders, 20, from Castleton in Gwent, will appear before magistrates in the Welsh capital on Friday, South Wales Police said.
Miss Morgan's family issued a tribute to her on Thursday, saying she was "a beautiful daughter, sister, granddaughter and auntie who had a heart of gold and would do anything for anybody".
They added: "She was taken away from us tragically, too soon, and has left a massive hole in our lives that will never be filled. Zoe will always be in our hearts forever and always. We are all broken hearted."
The bodies of window dresser Ms Morgan, of Llandaff North, and shop assistant Mr Simmons, of Grangetown, were discovered at 5.50am on Wednesday.
Colleagues broke down in tears on Thursday, their first day back to work since the double tragedy.
More than 24 hours from the deaths, there remained a sense of shock and disbelief that a young couple lost their lives on one Britain's busiest shopping streets.
Matalan staff in Cardiff were back at the Queen Street store this morning and held a tearful staff meeting before bosses decided to not to reopen for another day.
Workers later went outside together and tried to fight back the tears as they looked at the many floral tributes laid outside.
One simply read: "Lee and Zoe, you will be missed dearly. Rest in peace."
Hundreds of pounds have been donated to a JustGiving page in memory of Miss Morgan, describing her as "fun, sweet and exceptionally kind and honest".
She had recently graduated from the University of South Wales in June with an honours degree in fashion marketing and retail design.
It is believed Miss Morgan and Mr Simmons had been dating for four months and struck up a romance while working together.
Detective Superintendent Ceri Hughes said: "What happened to Zoe and Lee is an absolute tragedy. Their families are devastated. Our thoughts remain with them. This has shocked the community of Cardiff.
"We are still appealing for anybody who saw what happened to contact us if they have not been spoken to by police."
"We are very conscious that people who witnessed the incident may be traumatised. We can signpost those affected to a range of support services."