Disclaimer: Yugioh is the creation of Kazuki Takahashi.
Note: This story takes place post-canon, in the same universe as "...Whom the King Loves" (link in my profile). All you really need to know is that Yami didn't leave after the Ceremonial Duel, he and Yugi are a couple, and he retains his own body.
Yami's mouth moved leisurely along Yugi's neck, his tongue laving Yugi's skin in ways that made Yugi squirm with delight. A trail of kisses carried Yami up Yugi's jawline, until his lips closed over the lobe of Yugi's ear. Yugi murmured encouragingly, his hands clutching at Yami's back.
As had become his habit since returning from Egypt, Yami whispered half-heard endearments as they embraced, the words pressed against Yugi's skin along with Yami's lips, and tongue, and breath.
"…Mery-i…" A light caress of teeth and tongue against the shell of his ear.
"Mery nefer…" A nip that made Yugi gasp, fingers digging into the smooth skin of Yami's shoulders, pulling him closer.
Yugi blinked, his hands going still. Yami didn't immediately notice, his own hands gliding under Yugi's t-shirt, shoving it roughly out of the way as his exploring lips burned a path back along Yugi's exposed collarbone.
"You do know that I've been learning Egyptian, right?"
"So, you realize that I understood exactly what you just said."
Yami froze. Quickly, he replayed the last few minutes over in his memory. What had he…? Oh. Crap. "Oops?"
Yugi smacked him lightly on the shoulder, not hard enough to sting, but hard enough to convey his displeasure. "'Beloved' is nice. 'Beautiful' is weird, but I can live with it. But you are not calling me 'the king's ornament'!"
"It's an honorable title, beloved."
"It's a woman's title, Yami!"
"No… Well, yes. But I didn't use the feminine form!"
'That doesn't help!"
Yugi subsided with a put-upon sigh. He gave Yami's golden bangs an affectionate, exasperated tug. "Moron."
"I love you, too."
Yugi stared at him for a moment, then gave up -- and in. "Shut up and kiss me, you royal idiot."
Notes: Everyone keeps asking me what online translator I used for this story. The answer is: I didn't use an online translator. If you want to learn some Egyptian words (and the hieroglyphs that spell them out), I suggest the book "How to Read Egyptian Hieroglyphs: A Step-by-Step Guide to Teach Yourself" by Mark Collier and Bill Manley. It's an inexpensive, easy to use book that can be purchased through Amazon if you can't find it in your local bookstore or library. I urge fanfic writers to beware of using online translators and "dictionaries" as they can be misleading (especially if they don't give the hieroglyphs along with the transliteration).
Mery-i -- my beloved (the -i is the possessive pronoun)
Mery nefer -- beautiful beloved (the adjective always follows the noun)
Kheker-nesu -- The King's Ornament. The actual title is feminine (Xkr.t nsw), and was used for the king's concubines or the King's Wife's* ladies-in-waiting. The "t" on the end shows that the word is the feminine form.
*The ancient Egyptians did not use the title "queen." The king's main wife was the Great Royal Wife (hm.t nsw wr) or Great King's Wife, depending on how you prefer to translate it. The other wives were simply "hemet nesu" (Wife of the King).