Grimm isn't really sure how it happened but he's pressed up against a wall in one of the Palace hallways making out with Hallownest's new ruler. It’s not exactly an odd predicament, if the Hollow Knight is missing, they’re probably somewhere with Grimm. Everyone loves to blame him for distracting the king and Grimm is fine keeping how needy they get as his own secret. Ever since they learned to kiss Grimm, they were addicted.
He's not complaining.
His arms tighten around the Hollow Knight's neck, pulling them closer. Their hand is shaking on the wall next to his head and a small rumble leaves their chest. He draws his tongue across their mask, moving down to nip at where it meets their neck. Their claws scratch lightly at Grimm’s horns, petting him, adoring him.
"Impulsiveness suits you..." Grimm whispers, trailing a line of wet, hot, kisses from their neck back up to where their mouth would be. They push back into the kiss, nuzzling against him and quivering every time his tongue meets their shell.
They move their hand to write against his shoulder, " Does it? I'll remember that ." Suits them… they like the sound of that.
"Please do..." he purrs, leaving deeper kisses with tongue and teeth against their mask and down their neck. He pulls the neckline of their robes apart to kiss across their collarbone, leaving small marks with his fangs. They tug him up as soon as he starts to pull too much at their clothes, grabbing his chin and pulling him back to kissing their mask. Grimm growls and they pin him harder against the wall so he can't move, their hand pressing his shoulder against the wall. They want to kiss him more, deeper, harder. More. More. More.
Void tendrils dart out from under their mask, shoving their way into his mouth. He jolts in shock at the sudden feeling but as soon as he tries to kiss back, the tendrils retreat.
It takes Grimm a moment to realize what happened, face flustered. "Did Shade teach you that?" He asks, claws exploring the area were their mask and neck meet. There is no evidence that they could do that, but Grimm is intimately aware of how void can squeeze out of even the smallest joints. They tilt their head mischievously. He licks void residue from his mouth, "Do it again." He’s breathless already and the Hollow Knight can’t help but feel a sense of pride.
But the demand earns him some hesitation. " This is hardly the place, " they write.
He kisses them again, licking their mask, “No one is around,” he breathes. “Please?” They glance back behind them. The hallway is just as empty as it had been the whole time. When they look back at him, they take his face between their claws rather firmly.
“ Don’t move. I don’t want to hurt you. I’m… still learning, ” they write on the back of his neck, which makes him shudder. They had been an expert at using their void in combat, but this is… different. Grimm just purrs, licking their mask. They huff at the reaction, amused at how eager he is.
Slower this time, the void tendrils slip out from under their mask, leaving cool trails of void as they make their way to his mouth. He groans when they push inside and he tries to find a way to kiss back as they squirm and stroke his own tongue. The Hollow Knight shudders when his tongue pets against them, the temperature contrast almost making their knees buckle. He tugs at their royal robes and a low moan leaves him at the invasion. The tendrils practically claw down his throat, thrashing around in his mouth in a way that could barely be called a kiss.
And Grimm loves it.
Tasting Grimm makes them dizzy. They barely even tasted food they tossed in an eye socket or slipped under their mask. Grimm's taste is powerful and his salvia is hot and sweet. He's not new to their taste but he still kisses back with barely contained enthusiasm. He does try to hold still for them but it seems both are losing the fight as they become drunk off each other.
And the Hollow Knight wants to know how he tastes everywhere know that they have the ability to.
They pull back and he whines, wiping his face on the back of his hand. They are both panting and Grimm is the first to lean back in, trying to kiss them again. They catch his shoulder, pushing him back before they kneel before him. He gasps when they hook his leg over their shoulder and he can feel their cold face nuzzling his thighs apart.
“Ambrosia…” he growls, wrapping his claws around one of their horns.
“ Keep saying my name, ” they write against his thigh. He tries to get out a witty reply but the ice cold of their tendrils wraps around his cock suddenly. He hisses, hips rocking forward and their name leaves his throat in a breathy growl. Their tendrils seem to vibrate when he says their name and it makes him arch himself over slightly. The tendrils squeeze and stroke, darting over the head of his cock and even down to his slit underneath.
He tastes so much better than the Hollow Knight could have ever imagined and they rumble in pleasure.
The echo of footsteps sounds down the hall and they jerk up, hand next to Grimm’s head, shielding him from view with their cape. Grimm is panting, dazed. The Hollow Knight nods at the servants who pass them and once the group rounds another corner, they pick Grimm up and carry him towards their room. They barely make it as Grimm takes it upon himself to kiss and nip at every inch of shell he can reach. He’s practically dripping in their arm and his taste is still fresh in their mind, making them dizzy.
They try and write something on Grimm but their fingers shake and twitch as he gives their neck a noticeably sharp bite. Not hard enough to pierce but enough to make the Hollow Knight let out a low hiss. They barely shut the door behind them as they set Grimm down in front of their work desk. It's covered in paperwork they were supposed to be doing but instead they turn Grimm around and press his chest against the desk. Papers scatter as Grimm growls, claws searching for leverage as he raises his hips up.
The Hollow Knight almost wants to tease him more, seeing him face down and ass up, hips shaking in excitement and need. Almost.
They grab his hip, claws leaving marks across his carapace as they pull his ass up higher. Then, with a sharp thrust, they enter him. Grimm snarls, pushing back with force and begging without words. He manages not to cum instantly. If just barely as the Hollow Knight presses their chest up against his back. The full body contact makes them both shudder. Grimm is fire and the Hollow Knight is ice. They thrust just slow enough not to cut the experience short with their own orgasm.
"Ambrosia," he chants their name, reaching behind him and blindly trying to grab their hand. Their hand is shaky as they move to grab Grimm's, intertwining their fingers and squeezing. At least one of them can be quiet because Grimm is doing a wonderful job at alerting the whole palace. Really, it wouldn't change much if he could be quiet because the obscene, sloppy, noise of his cunt it enough to seal any doubts of what they are doing. The Hollow Knight feels him tighten and moves their claws to rake down his back. It's all the answer he needs.
Grimm moans, vision blurring as he tries to muffle voice against the desk. He cums messily, body convulsing as his temperature reaches its peak. The Hollow Knight, on the other hand, shudders silently. They follow Grimm over the edge with a rush of cold void, pressing their face to his neck.
They stay together like that for some time, panting and ruining the paperwork under them before they unsheath themself from Grimm. They pull him upright, holding him in a tight embrace as they move him to the other side of the desk and gently set him into the chair. Then, they go to try and check over the cum-splattered papers.
Grimm smiles sheepishly, "Sorry…" he whispers, picking up the papers that had fallen to the floor, "What kind of mess had you gotten yourself into?" He motions to the papers, "Well, before me, that is."
They place a hand on his lower back, " Approval of razing old structures so they can be rebuilt ," they write, " I'll get new copies drafted, given how we… " they pause, glancing across the desk, before reaching to tip over an inkwell. They return their hand to Grimm's back, " Given how I spilled ink over all these copies. "
Grimm can't help but chuckle, draping himself over their back and wrapping his arms around their neck. "Thank you," he breathes against their neck, "For making time for me. You could have easily turned me down."
" I could have. I ought to work on paperwork ," they write the words gently against his arm around their neck.
" But impulsiveness suits me ."