"Halt! Who goes there?" Papyrus had his spear at the ready. This is the moment he had trained for. He could finally show Undyne how good a guard he was. Papyrus heard a quiet laugh as fog began to form around his feet. "Err, Show yourself or face the wrath of the Great Papyrus," The mist had swallowed Papyrus up to his chest, he began to feel dizzy. "What's happening? HEL-"
Gaster opened his eyes. Or, Papyrus' eyes. They were usually a nice, orange colour, but Gaster had turned them black ink. He inhaled slowly. "Finally, a physical form once more," Gaster inspected his new body. "Skeleton, tall, horrible fashion sense. I suppose it will do."
"W-who are you?" Said Papyrus. His eyes flickered orange.
"Fuck, you're concious? You don't need to know. I'll only give you your body and soul back if you shut the fuck up," Payrus' eyes were back to their pitch black state. "Since you're a skeleton, you must have..." Gaster felt a growing object in Papyrus' pants and smiled. He rubbed the bulge, making sensual sounds. Hedropped Papyrus' pants down. "An ectodick... You lucky bastard.". Papyrus' hands clutched his dick hard. He began to squeeze it. Gaster heard Papyrus flinch in pain. "So you feel what I feel? Interesting..."
Papyrus started wanking. Gaster was fascinated at how his gooey dick felt. "What are you doing?" Papyrus said.
"Having some fun with you." Papyrus had his two hands around his dick.
"Stop!" Papyrus took control of his body back, but not for long.
"Don't even try. I own your body and soul, I could jump off a cliff if I wanted to. Now let me wank, then I'll free you." Papyrus obliged and allowed Gaster to seize control of his body. It felt weird, having someone else control him and not being able to do anything. All he could do was watch as Gaster wanked. Soon, he saw a white liquid travelling up his translucent dick. He and Gaster moaned in unison until Gaster stopped abruptly. The stream of cum slowly slid back down his shaft. Papyrus complained. "What? You thought I was gonna let you cum? The better it feels, the stronger the transfer will be." Transfer? Papyrus was going to question it, but decided it was better not to.
The process continued. Gaster would tease Papyrus to the edge of an orgasm, but he would always torture the skeleton by not letting him cum. "P-please, I'm begging you." Cried Papyrus.
"I'll let you cum this time, just say 'Daddy Gaster, let me cum and I'll give you everything" Gaster rubbed the tip of Papyrus' dick, tickling him.
"Daddy G-Gaster, let me cum and I'll give you ever-everything." Papyrus said weakly.
Gaster chuckled. "As you wish" Papyrus began to wank. This time, he began moaning much faster.
"AH FUCK, KEEP GOING" Gaster sped up and soon an explosion of cum came from Papyrus' dick. The cum covered the floor and Papyrus' bones. Suddenly a small, orange heart appeared from Papyrus' chest. "My... my soul."
"No," Gaster panted. "Mine" The heart turned black, and Papyrus screamed. "Bye, Pap." Gaster stood up and walked away, towards Snowden. He saw Sans standing there.
"Hey, bro, something up with your eyes?"
"I just got... contacts."
"Hmph, black eyes suit you" Sans smiled. Gaster hugged Sans tightly, rubbing his hands along his back.
"Woah, you ok?"
"What? Can't I hug my brother." Gaster said
"Its not that, you're just acting different. I kinda like it though. C'mon in, Alphys made hot cocoa." Gaster put his arm around Sans' shoulder and walked in. He heard Papyrus in his head, crying. "I love you, bro."
"And I love you." Gaster smiled as he walked inside.