A small snapshot into Yuugi and Kaiba's love life probably set after the "Dark Side of Dimensions" movie (no spoilers), because I love Rivalshipping but there's not enough fics on them T-T. This was inspired by a post I saw on Tumblr. I'll link it if I can find it. I hope this is good and as canon-ish as possible. Enjoy and leave a review if you liked :)
Title: Big Spoon, Little Spoon
Rating: M
Warnings: Mentions of sex, homosexuality
The moonlight shone in through the large glass doors of the balcony, illuminating the spacious master bedroom in its white glow. The beam basked the bed in the center of the space in its light, causing one of the two young men on it to smile. He snuggled in his partner's hold, the second man nuzzling his neck almost shyly. Yuugi, the shorter of the two, played absently with a strand of his lover's hair as he sat naked on his lap. His skin was still flushed and his heart was settling to its normal pace after their activities moments ago. He chuckled and loosened his legs' hold around the other man's waist, shuddering subtly in residual pleasure as he moved off the comfortable lap he was seated in. Seto, his partner, frowned in his usual fashion and laid back on his large bed, eyeing the delicious view of Yuugi's backside as the younger leaned over the bedside to reach for their discarded boxers.
Flinging his underwear at his lover, Yuugi laughed as it hit Seto in the face before the shorter man slipped on his own boxers after cleaning himself up with some nearby tissues. Seto rolled his blue eyes and dressed in his shorts, mumbling something akin to 'my boyfriend is a child'. He still hugged Yuugi tightly as the latter crawled back beside him to cuddle. The shorter of the two rested his cheek on his partner's chest and sighed contently, feeling himself relax in the afterglow of their lovemaking. Seto again grumbled about wanting to take a shower, 'because feeling sweaty and gross after sex was NOT romantic', but Yuugi slapped his chest, mumbling back for him to stay put. Seto rolled his eyes once more but complied, the compelling hold his smaller lover had over him winning in place of his compulsive need to be clean. Yuugi looked up at Seto and grinned, his deep purple eyes shining, before leaning closer to peck the other's lips in reward. Seto suddenly could care less about a shower as he smiled a bit into the kiss.
The two lovers cuddled until sleep pulled at them, Seto drifting off before Yuugi due to his long hours at work that day. The latter found himself tracing shapes in the former's chest as he closed his eyes, thinking absently about anything and everything. Yuugi's mind filled sleepily with thoughts of work at his grandfather's shop the next day, wondering if his elder was lonely with his grandson now living mostly at the Kaiba estate. The shorter man knew that his beloved grandfather was likely alright despite Yuugi's lacking of presence at home, especially with the latter making a point to visit at least once a day. The older man also had an assistant helping him when Yuugi wasn't there, at Seto's suggestion and awkward show of concern for the elder Mutou.
Smiling gently, Yuugi opened his eyes and stared up at his partner's resting face. He pressed a kiss to Seto's cheek before settling down to sleep. Suddenly, the taller of the two turned in his sleep and pulled away, flipping over on his side facing away from his lover. Yuugi huffed and pouted instinctively, blinking at the sight of Seto's broad back. "I wanted to cuddle..." He crossed his arms, peeved, and hoped the other man would somehow hear his request in his sleep, but he didn't. Huffing again, Yuugi moved closer and hugged Seto around the waist, spooning his taller lover from behind. Sighing happily, Yuugi was perfectly content to cuddle his boyfriend from behind. The 'little spoon' is now spooning the big one, he thought and chuckled quietly to himself. Closing his eyes again, he buried his nose against Seto's warm skin and let sleep lure him again. As he dozed off, he felt Seto's hand take hold of his over the latter's stomach. The subconscious display of affection made him smile in his slumber.