So the very next day the 26-year-old Canadian singer's ex-girlfriend, Bella Hadid, unfollowed the Hands To Myself songstress on Instagram Wednesday afternoon.
The surprise new couple were not shy while hugging and sharing a sweet smooch in public as they left celebrity hot spot Giorgio Baldi in Santa Monica, in photos posted by TMZ.
The Weeknd recently split from Bella, 20, in November after dating for two years.
Selena, 24, and the younger sister of Gigi Hadid are also both members of Taylor Swift's girl squad.
In screenshots posted by Elle, Bella was still following Selena at 1:30 P.M. but less than two hours later the actress and singer was unfollowed.
The brunette beauties were even pictured together in September 2015 as they posed for an Instagram snapshot with model sisters Suki and Immy Waterhouse.
The former Disney Channel starlet - who holds the record for the most Instagram followers by a celebrity with 106 million - still follows Bella, who holds 9.5 million.
The Victoria's Secret model is one of just 254 people Selena follows on the popular social media app.
On Tuesday night the pop starlet held onto the Starboy hit-maker, wrapping her arms around him as they left the restaurant.
Selena laughed and smiled as she planted kisses on her new man, with The Weeknd - real name Abel Tesfaye - at one point moving in for a full-on smooch.
Each was dressed in jeans and jackets with the R&B star adding a baseball cap. The Weeknd split from Bella Hadid, 20, in November after dating for two years.
Selena, of course, had a long on and off again relationship with Justin Bieber before they split for good in 2014.
The successful singer is fresh from touring her platinum-selling 2015 album Revival and recently completed a stay in a Tennessee treatment facility getting help for 'anxiety, panic attacks and depression' - which were side effects of her Lupus.
In December, Mexican pop star Paulina Rubio revealed that she and Selena have already collaborated on new material for the star.
Last month she was named as the new face of American fashion brand Coach in a rumored $10million deal.
Meanwhile, The Weeknd is featured on the cover of February's issue of GQ magazine, along with Chance the Rapper.
