This idea has been in my head for years. I didn't do Mario's point of view, because I thought Sonic 's would be more interesting.
I m working on two more stories. So It ll take me a while. Hope you enjoy!

"I smell-Peach's cake?" Sonic said, as he woke up. As he get from under the covers, his ears perk up, his eyebrows flipped, and his mouth opened up in shock. He was in Mario's room.
Solid red painted walls all around the room, a treasure chest was sitting right next to the small closet. Sonic got up he still had his shoes on. He walked to the treasure chest and opened up, it was full of coins. Sonic closed the chest ,bust through the door and rushed downstairs.

When he went downstairs, everything wasn't red and brown anymore. It was white and pink. Sonic walked into the dining room. Pink curtains tied in twins so you could see outside the huge windows. "Oh, Sonic" Peach said putting the cake in the refrigerator, "What are you doing here." She was dressed in her usual pink dress with a sapphire in the top section. Sonic shrugged his shoulders, "I don't know how I got here". Peach's phone rang. Sonic picked it up. Before he can even say "Hello", he heard Mario moaning " Who switched us? I'm in Mobius and I don't see Sonic." "I'm Sonic, in your world." Sonic replied.
"Oh mother"
"I'll take your place"
"Fighting Dr. Eggman's hard without-a you"
"Don't lead as much openings"
Mario hung up.

Peach took the cake from the fridge. It was vanilla two layer cake. Sonic went in a drawer and took out vanilla icing, "Lemme help"
Peach took out the strawberries and finally closed the fridge.
Sonic took out frosting and closed the drawers. "The knives are over there, Sonic" Peach said pointing to the wrapped napkins "Grab one and help me apply the frosting" Sonic did as told. He dropped the knife into the icing and spread it all over the cake. Peach giggled, "A little slower, please" Sonic's ears flopped down, "Whoops" he said, applying the icing a little slower. 10 minutes later, both layers were filled with icing. Sonic grabbed the strawberries and said, "Can I cut the strawberries?". Peach grabbed the frosting, "Leave one and cut the rest into eighths". Sonic did as told. He put them on the sides of both layers. Peach was done outlining the cake with strawberry frosting. She picked up the remaining strawberry and put it on top of the whole cake. "I'll put this in the fridge so the icing and strawberries can sit in" she then said. Sonic didn't know what "sit in" meant, but didn't asked.

Sonic walked outside to walked around the castle. When he got to the back of the castle. He heard Peach's scream for help.