Alma smiled, running one hand through Kanda's hair as he lowered himself into the bound man's lap. "Come on, Yu, don't you trust me?"
Kanda snorted, pulling his head from Alma's grasp. "Hell no."
Alma leaned in to nibble at his neck. Kanda stiffened, pulling the ropes around his arms and hips taut. He pulled away, but Alma just followed, licking the blood from the now-healed cut on his chest. Through the mess of his hair, he could see Alma's tail waving from side to side already, and Kanda had nowhere to go when Alma's hand snaked up behind his head and gripped his hair, tilting his head back towards the ceiling. He jerked, knocking an elbow into Alma's face, but the Akuma who had once been his best friend just smirked and leaned in to kiss him.
Alma's breath was abnormally hot on his face, but Kanda didn't get much time to think about that before Alma's lips were pressed against his, a tongue trying to push his mouth open. Kanda tried to pull his head back, but it was impossible with Alma's hand against the back of his neck, and eventually he stopped resisting, letting Alma kiss him long and hard enough that he started to feel breathless from a lack of oxygen.
Alma let him pull back then, clawed fingers pulling themselves free of long black hair to scrape across Kanda's shoulder - not drawing blood this time, but definitely leaving painful red marks that made Kanda shiver. Stupid Alma, taking advantage of his masochistic streak.
"Damn, Yu, you taste so good..." Alma murmured into his ear. Kanda let out a "hmph" in response, not at all willing to admit that Alma's taste wasn't something he really minded, either. It still had nothing on soba, after all. Alma made a "mmmm" noise against his chest; not quite the strange purr that had almost become familiar to Kanda, but definitely coming close.
Alma's tail was sliding around his waist, now; the sharp tip left a cut just above his hip bone, drawing more blood that Alma ran a finger across greedily. Kanda glared at Alma as the other male grinned and stuck his fingers in his mouth, happily licking the blood out from under his claws. Meanwhile, the tip of the tail slipped down along the inside of his leg, and Kanda jerked against the ropes around his hips. He bit his lip as Alma leaned back against him, one claw marking little circles on his back.
"Yu, you're so quiet. If I didn't know better, I'd almost think you weren't enjoying yourself."
"Fuck you," Kanda muttered through gritted teeth, as Alma slipped a hand down between his legs. A quick slice; four or five cuts against the inside of his leg, and Kanda did moan then, rolling his back and pulling against the bonds. Alma smirked.
"Yeah, I was planning on that.” The section of tail around the back of his waist tightened, pulling his hips forward towards Alma. Kanda's knees were sore from the ropes only partially supporting his weight, so it was hard to not relax his body into Alma's hold. The hand that wasn't otherwise occupied trailed down his shoulders and back, making him shiver.
Kanda hated being helpless like this, but he'd be damned if he was going to show that weakness to Alma. The Akuma would probably stop the moment he asked, if he asked, but they were both far too stubborn to admit it. So their hips pressed together and Alma kissed him again, even as Kanda felt the slicing pain in his lower abdomen of the tip of Alma's tail sliding into him.
Alma moaned into his mouth then, claws digging deeply into Kanda's shoulder, and the combined pain and pleasure made Kanda go completely limp in his bonds. Alma's tail squeezed around his leg, the tip digging deeper even as Kanda's body tried to regenerate around it, and Kanda closed his eyes, hips rocking forward and back desperately for release.
Alma was doing his best to keep him from it, though, and the tail inside him stilled entirely as the Akuma dug his claws all the way down Kanda's back, leaving long bloody marks. Kanda pulled his head free of the kiss to moan into Alma's shoulder, and before he knew it he was biting down hard, Alma's blood in his mouth. The Akuma virus burned his mouth, which just made him dig his teeth in harder, and Alma murmured something against his neck before biting own himself, a hole in Kanda's windpipe that drew the man's own blood up to mix with Alma's in his mouth.
The tip of the tail was in motion again, and Kanda felt himself go over the edge, pressing himself against Alma so suddenly that the ropes dug deep red lines into his hips. He was vaguely aware of Alma purring and smirking at him, nuzzling his shoulder slightly as Kanda went limp again, all his struggling completely spent. The wet feeling around his legs was only increased when Alma carefully drew his bloody tail out.
"There, that wasn't so bad, was it?" Alma said as he pulled away to start undoing the ropes, grinning like an idiot.
Kanda had just enough energy left to spit blood in his partner's face.