The 26-year-old musician – real name Abel Tesfaye – has been reportedly romancing the 'Hands To Myself' hitmaker since the pair were spotted locking lips earlier this month, and it has now been claimed the pair talk "every day" and have a "sexy and flirty relationship".
A source said: "He really likes her. They text every day. They have a really sexy and flirty relationship. They laugh and like each other's personalities."
And whilst it seems things are quickly heating up between the pair, sources insist they are "just having fun" for the time being and aren't getting too serious.
The insider added to E! News: "As of now, they are just having fun and enjoying each other."
Their budding romance might seem to be going smoothly, but it was previously claimed the 'Starboy' singer was holding back from the 24-year-old popstar when they were pictured kissing outside a restaurant in Santa Monica.
Body language expert Dr. Lillian Glass said of the pictures: "His body language says he is holding back.
"When she's kissing him, his expression says it's too much. He's also looking in a different direction.
"When couples are looking in different directions like this it signals that they are not like-minded."
Despite Abel's reservations about moving too quickly with his new relationship – which comes just months after he split from model Bella Hadid – Selena is reportedly "happy" with her new beau as he "makes her feel secure".
A source said: "She is happy and doesn't mind sharing that with the world.
"Abel makes her feel secure and Selena has nothing to hide. Selena gets passionate about things real fast and that is exactly what she is doing with The Weeknd.
"She finds him charming and is enamoured by the person he is and the way he presents himself to her."