This Tony’s Avengers formed to stop a threat much like in the Avengers movie, Evil Alien Overlord comes to free poeple from freedom and blablabla. But it’s important to note that the catastrophe that joined this group together wasn’t the same as the Avengers movie. There were other threats which were more supernatural. And, Thanos wasn’t the main force behind this attack.
Besides the different enemies, they had a different ally. The god of mischief himself, who perished after the battle, having had injuries of his own previously. He wasn’t going to let himself die on the spot, though, and so Tony Stark became a host for his soul and power…
This partnership can have its ups and downs, being responsible for somebody else did stop Tony’s most dangerous self-destructive tendencies. They would resurface occasionally, but this events are way more far-in-between, and Loki always manages to calm him.
Loki’s, for the most part, a doormat, making himself apparent rarely, and even more rarely physically. He’s tired and jaded and though he hides it, the time he spends “sleeping” is inmense. He can make himself apparent as Tony’s reflection, changing it to resemple him, wasting less power that way.
They still act like themselves, but each one’s knowledge is for the other so share. Loki now knows how to drive, pop-culture, the lyrics to Metallica’s songs. Tony’s more cultured. But the most important thing would be Tony’s knowledge of magic and Loki’s knowledge of technology. Tony, can’t cast spells as of yet, but it would make anyone raise an eyebrow if you saw him identifying a rune. Oh, but he can’t shapeshift. This would seem very odd, should anyone know.
This Loki, as you can see, is a good guy, a hero. Kind of. This doesn’t mean he didn’t do some awful things in the past, which he paid for in injuries that did cost him his life. And it doesn’t mean he’s not devious.
Loki can take over Tony’s body, when he feels the need. He’d much rather keep sleeping, though. He’s so very tired.