Loki and Tony have already met in Hela's realm, when both of them had a brush with death. They don't remember each other until they are close to death again, (which is quite frequent with them tbh). Bonus points if Hela is fed up with the situation and gives them their death memories to get them together once and for all.
Hela would just be like “Oh for fucks sake you two again. The last time you two were together you broke my favourite skull decoration with all your screwing around. Here just remember and gtfo of Hel.”
Great prompt, anon, thank you! :)