Its a subculture of comfort and selfcare. Alex-core represents the act of wearing an oversised comfy lounge clothes (preferably an Oodie or oversised hoodie), and snuggling up on the couch with a fresh cup of warm tea. The tea must under no circumstances be reheated in the microwave.
I'm going home after work, and I'm going to go live my best alex-core life for the rest of the day.