After defeating Thanos, almost everything for the Avengers went back to normal. Almost. The team was bigger than ever, and so was the building.
Loki thought that when he joined the Avengers he and Thor would spend more time together, side by side as real brothers. Thor, on the other hand, was busy with the new Avengers, like Carol Danvers, Groot, Rocket and the suddenly returned Quicksilver. This makes Loki feel lonely.
This story starts with Loki, who's at a party, drinking to forget.