Relate
Thor reached out to the Chitauri Sceptre stopping midway as it gleamed under the Quinjet's lights. Gleamed just like it had in the sunlight when Loki wielded it against him. It elicited memories of how graceful Loki was. Of the relief that he had felt when for a single moment those eerily blue eyes had returned to their proper, gorgeous, emerald. Briefly he remembered as well the illicit pleasure they had shared amidst the softly rustling trees and swooshing waterfalls of Nornheim.
Perhaps they could have returned there if only Loki had helped him instead of fleeing after their battle at Stark Tower. If Loki had and the sceptre were still lost he and Loki could have recaptured it themselves. How he missed the darker humour they had sometimes shouted as encouragement in the heat of battle. One of his favourites still being Loki's, "Oh, come on, Thor if I stopped killing these bandits to find and make love to a draugr I would still finish before you. Even the corpse would finish before you !" from when they were barely three hundred years old.
While Stark was similar to Loki in dry humour and Romanov in her practicality it wasn't the same without the master of magic to berate him for saying that summoning the elements was not magic. Without Loki to chide him for near always charging into battle like an enraged bilgesnipe. He missed being able to relate his feats and not have to explain what every second word meant. Missed the rush of fearful excitement that came with facing down a fourteen strong band of brigands that rode on armour-clad mountain lions. Just as he wished that someone else could understand the beauty of Asgard which when lit by fireflies in the gloaming was so great that even he noticed it. The Midgardians mental images had not the power to relate even half of its majesty, much less its entirety.
Slowly he lowered his hand and stared at the blue crystal ensconced by the halves of the sceptre's curved blade. It had pierced Coulson's chest as the Kursed Dark Elf had pierced Loki's with the dagger. Even if the sceptre had not been too powerful for the Midgardians he would have taken it with him because it was the last thing on Midgard that Loki had touched. Dimly he heard Romanov calling his name, asking his opinion of something to do with Banner's skill in battle. He had to protect the sceptre from harm and misuse as he had not managed with his brother, as Loki had not returned to Asgard the sceptre had to. It had to because it was all that he had left.