"Whoa! I didn't know you had a bunch of those sweaters, cous," exclaimed Evan.
"Well, I do," Luke answered. "It's a long story, I'll tell you later."
"But for now, if you want, Zack doesn't have a partner," said Mark.
The twins decided to change out of their two-headed sweater so that Zack could be a part of the experience, but more than just the two-headed experience. So they pulled one of the four-headers out from the pile, and the twins put themselves at either end inside it. Then, Zack and Evan slipped between them and popped their heads through the holes. The groups were now Ethan and Scott in their two-header, Luke with Kevin, Allan, and Dean in a four-header, and now Mark, Max, Zack, and Evan in a four-header of their own.
"It's nice to be doing this again, Zack," Evan smiled. "I really enjoyed doing this with you the last time I visited Luke and his dad."
"And now you're doing it with me and my older brothers!" Zack replied.
"Okay, everyone," said Scott. "What do you guys wanna do now?"
"I feel like Mark and I should go up to our room to really connect with Evan," said Max.
"I'll go with you guys," said Zack, "not that I really have a choice right now."
"Sure thing, little bro," Mark replied. "The more, the merrier!"
"I feel like just relaxing down here with Kevin, Allan, and Dean," said Luke.
"In that case, son, Scott and I will be downstairs in his basement if any of you need us," Ethan replied.
With that, the three groups went their separate ways. Luke-Kevin-Allan-Dean stayed in the living room and sat down on the couch, Ethan and Scott went down to the basement, and Mark-Evan-Zack-Max walked up the stairs to head into the twins' room. They each did their own things for a while, their bonds growing stronger with each moment they were together.
Then, suddenly, a scream rang out from upstairs. Luke was so startled, he tried to get up from the couch before the others did, forgetting that he was inside a giant sweater with them. Once all four managed to get up, they quickly moved to the stairs just as Ethan and Scott ran up from the basement. The two groups hurried up the stairs and got to the twins' bedroom, where Luke knocked on the door.
"Don't come in!" It was Evan's voice.
"It's alright, Evan," said Zack's voice. "We all already know about this kind of stuff."
"What?!" said a startled Evan.
"Like Luke said, it's a long story," said Max.
"Just come in," Mark called out. "But be prepared for a bit of a surprise."
"As long as you boys aren't naked," Scott answered.
Luke turned the knob and opened the door. The six of them entered the bedroom and saw the twins, Evan, and Zack. The four of them were still wearing the four-headed sweater, but they were no longer smiling, and Evan looked a little freaked out. It didn't look like any of them had reason to be freaked out about anything...at first. But then Ethan noticed the boys' pants--there were only five legs instead of eight, and it looked like their four pairs of pants were merged into one! It did not take long for everyone to put two and two together, and to figure out that that is exactly what happened. Luke reached out and lifted up the sweater, and he saw not four shirts, but one fused shirt with four head holes. Mark, Max, Zack, and Evan were now conjoined siblings for real!
"What the--?" exclaimed Kevin.
"You okay, Evan?" Ethan asked.
"I thought we told you boys not to do any fusion until further notice!" Scott growled at his sons.
"How did this happen?" Luke asked. "The three of you have fusion powers now: which of you caused Evan and the others to fuse with you?"