"Papyrus, I don't know how your brother would feel about this.." Undyne murmured into the honey scented hoodie that wrapped up the skeleton's bare bones, hands braced on her lower back to keep her close.

"Maybe not, but he knows I love you." Papyrus said softly, laying close to the scientist in his room, the sheets of his bed spread halpazardly, the only clean in the entire room was the bed, only cleaned off to be used.

"But.. You know how he gets when you just hold my hand.." She whispered, her voice cracking as she hid her tears, searching for a scrap of warmth in Papyrus' chest.

Papyrus sighed sadly, nuzzling her fin gently to reassure her, his seemingly impossible breath hoy on her scales.

"Hey, hey, it's alright. I'll never let anything happen to you, okay?" He said as if certain, though his empty eyesockets said a different story. Undyne read his expression like a book.

"Y-you're scared.." As she spoke, Papyrus lowered his gaze, recognizing the tremor in her shoulders and stutter in her words, only becoming noticeable when she felt uncomfortable or fearful.

"I'm just worried. I don't want to force you to have this life if we want to be together. It's not fair to you, to be scared of my brother whenever you so much as think about me." Papyrus fell silent as Undyne took in a shaky breath, knowing well she was crying.

"We.. w-we can't j-just.." She couldn't finish, but Papyrus knew what she meant. It had been on his mind ever since he first asked her to be his girlfriend.

"Yeah.." He didn't want to suffer through it anymore. His expression hardened and he shifted slowly so he was above Undyne, his pelvis bones pressed against her waist, light enough as to not induce pain.

"P-papyrus?" She whimpered, her hands clenching his sweater, never wanting to let go of the pun-loving monster it belonged to.

"You want us to be together, right?" He asked in a stiff tonw, the serious look on his face sending a chill along Undyne's spine. She nodded, beginning to understand his motives.

"We've never done this before, and it's considered the greatest act of love in the underground, right?" Again, she nodded, peering up at Papyrus with a sad, shaky smile, sniffling as she adjusted her grip on him.

"Than we need to do this. We need to show him that we're together, we love each other." Undyne agreed, if a bit nervously. She didn't know how to feel, excited or even more scared.

What would happen if Sans caught them?

Would she live to share the moment with Papyrus, the sealing of two souls amonst the many others, the act of endless devotion?

"Yes." She caught Papyrus' look, nodding still. "Yes."

He smiled softly, an orange blush spreading across his cheeks to match her red.

"Okay." He said nothing else as he pushed down his shorts slowly, peeking as Undyne undid her jeans. She noticed and gave him a look, though he shrugged halfheartedly, a quirky grin in his skull.

When they were fully unclothed save for her bra and his hoodie, Undyne locked her legs together timidly, her hair shielding the fear in her eyes.

Papyrus swept away her bangs and kissed her temple softly, memorizing the cold smell of dew that resignated from her.

"It's going to be okay." He whispered, closing his eyes as he heard her whimper, gently finding his way inside of her.

The pleasure was immediate for him, warmth seeped onto his member and he let out a breathy groan, enough to get another look from his girlfriend, though this was pained.

"It hurts, Papyrus.." She whined softly, her insided stretching as his member slid in further.

"Don't worry, I promise it will feel better.." The comment calmed her and she scrunched her face, holding back a yelp as her seal broke, a small stream of blood dribbling out of her entrance.

"Shh.." Papyrus stopped when they were connected completely, meeting her gaze with a sympathetic smile.

"Papyrus.." She whispered, tears streaking down her cheeks from pain and emotion, unable to stop either.

Papyrus pulled a thumb along her scales to wipe them, cleaning her cheeks softly and laying gently kisses in the tears' place.

"I got you.." He whispered, taking her hand in his own, positioning himself correctly to move.

After a few moments of adjust, Undyne finally nodded, closing her eyes and turning her head away as Papyrus moved slowly, gulitstricken from her small gasps and whimpers.

After a bit, he was happy to hear a soft moan, his soul stirring with lust at the sound of it. He moved faster, startling the scientist who tightened her grip on his fingers entwined with hers.

She looked up at the skeleton, words escaping her mind as their joy and pleasure increased.

"I love you.." Papyrus muttered between lengthy groans, his bones shaking from delight.

Undyne's eyes were filled with ecstacy as she moaned quietly, her lips parting to speak the words back.

Papyrus waited but never heard them, worry spreading onto his features as Undyne's body became slack, stopping as he touched her cheek.

"Undyne?" He becamw scared as her hand fell limp in his own, searching her dim eyes as a small puff of air escaped her for the last time.

It was only than did he see the stark white of bone marrow crested red that mounted from her stomach, torn through her body like a knife through a tomatoe.

Papyrus' eyes widened in horror and he felt tears stream down his face, his fingers shaking as he touched his dead love's face, his breath short and scared.

"Undyne.." He managed to choke out, his soul sinking as it realized the hopelessness in it's owner's thoughts.

Papyrus' bones stiffened as a soft snicker arose behind him, noticing the long shadow spread across the floor with a shaft of light from the open doorway.

He didn't want to look, but something forced him to.

"Aww, what's wrong, Papy? Did you get to cum in her?" Papyrus stared blankly as Sans stepped forward, his boots padding across the carpet, lifting in a childish manner similar to a halfskip.

"Sans.. Y-y-y..." The older skeleton was speechless, his gaze returning to the blood that seeped from the deadly wound in his girlfriend's body, panic erupting in him as he watched her filter into dust.

Sans smiled and swiped a hand through her remains, rubbing his fingers together as it tainted his baby blue gloves, a playful sense of insanity present in his lit up eye sockets.

"Why.." Papyrus sobbed, dropping into the dust and trying to gather every remain, clutching the lab coat that was the only thing left of his soon to be soulmate.

"Because, big brother, I can't have anyone stealing you from me," Sans said sweetly, gripping Papyrus' chin in his dust coated han, holding his brother's skull up so he had to look at him.

Papyrus was too lost to reject or retaliate, breaking down into submission as Sans narrowed his eyes, smiling innocently at him.

"And you're mine."