Bridges
Heimdall and Loki (and others) interact. Somewhat in chronological disorder due to the constraints of the electromagnetic spectrum.
Standard disclaimers: Characters and situations belong to Kinoshita Sakura, Snorri Sturluson and whoever wrote the Lokasenna and the Voluspa. Some interpolations are my own, as are all errors. Norse gods, as always, belong to themselves.
Red
The first time Heimdall sets eyes on Loki Laufeyiarson is in Gladsheim. It is rare for the Watchman of the Gods to be summoned away from his post to Odin's hall of rejoicing (or indeed any of the others' dwellings), but this is a special occasion. Loki stands next to Odin as his blood-brother, and all Heimdall observes at first is the red hair, clothes and eyes of the newest member of the Aesir (jotun, a whisper only he can hear). It is only much later that he sees the fire in those eyes, burning at him.
Orange
All the gods laugh at Heimdall's suggestion (except Thor who looks mightily affronted), but it is Loki who persuades the Thunderer to don a wedding dress, and promises to accompany him to Thrym's hall. Heimdall watches the chariot drive off (Thor's rumbling can be heard even by mortals below), and he cannot repress a smile when Loki, resplendent in his saffron bridesmaid's robes, turns to wink at him from a suitable distance.
Yellow
The golden mead is rich and heady, and with every cup, Loki's insults grow increasingly vicious; and after particularly violent taunts directed at Freyr and his servant, Heimdall feels obliged to say something, though Loki seems to have overlooked him thus far.
"Why don't you stop this, Loki? You're drunk, and not yourself;"
"And you, Heimdall, are doomed to stand guard at the Bridge forever; but later I shall be sober."
Loki turns back to his mead and the rest of the company, the dull light of the fires glowing in his hair, and Heimdall thinks of bright copper glints and dancing eyes in the sunlight.
Green
Loki's eyes are a more appropriate colour for a human child, though they are still as unfathomable as he remembers. On the other hand, it was never Heimdall's intention to blend in, since he expected to be here only for a while, but it seems that his plans have to be changed. He takes down a book from one of Hel's library shelves, since there is nothing else to do, and opens it at random.
"O, beware, my lord, of jealousy; it is the green-eyed monster.."
He does not hear her until she is standing right behind him.
"Father's mortal girl is here."
Blue
He is not always pleased to be compared to the Vanir, since those of their number whom he has had the privilege to know personally are occasionally, in his opinion, ungodly. Especially a certain fertility deity, whose crackpot schemes, strange fascination with sales and mechanical objects, ridiculous dressing (a blue cape? in Japan?), and frankly poor taste in women (a giantess, rather than all the goddesses in Asgard whom he could have picked, and that girl) he has had to endure for the past several months. Time passes too slowly for his liking. Though sometimes, as he sits peacefully on a grassy knoll next to Freyr, watching the clouds pass, he wishes that it would stop, if only for a while.
Indigo
He watches her board the train, silhouetted against the dark sky. She is bitter, like him, and has more reason to be so, cast into the shadows before she understood what was happening. He hopes that she will find what she has been searching for, though he knows that she has ceased to hope. She smiles as he turns his back on the departing train.
Violet
"You know, your hair and eye colours clash."
That is the first thing the trickster (appearing suddenly on the bridge, right in his path) says to him, and it is not quite what he expected (though he should have expected the unexpected, with Loki). And though he now knows what to expect at Ragnarok, he is content, for now, to let Loki surprise him.
Notes
Jotun: Norse word for giant – technically speaking, Loki is one of the Aesir only by "adoption"
According the Lay of Thrym, Heimdall was the one who came up with the idea for Thor to dress as Freya to retrieve Mjollnir from the giant Thrym.
Apologies to Winston Churchill for appropriating his retort for Loki's reply – I like this better than the one in the Lokasenna.
Sorry also to the Bard for misuse of the quote from Othello.
In the Lay of Thrym, Heimdall came up with the above suggestion re: Thor because "Like the other Vanir, he knew the future well". Of course, since all these are drawn from sources of unquestionable antiquity (but dubious integrity), the accuracy of the comparison is doubtful (as anime!Heimdall would agree).
Snorri mentions that Heimdall wasstruckby a head (at Ragnarok, where he and Loki kill each other, therefore this waspresumably Loki's head), and the name of his sword was Hofnung ("man-head"). Since the origins of the etymology are lost in time (and I am unable to bring myself to write any R-rated fic), I have chosen not to bring this to its bawdy conclusion.
