This was a commission done for
Beerus was on the look out with Dende, taking about "God-stuff", but in all actuality he had ulterior motives. Today, he was going to taste what he heard was the GREATEST ICECREAM ON EARTH... and he made sure that a certain Majin wouldn't get his hands on it and provoke him again. To be honest, Whis actually informed him about it, and he asked Dende where he could find it, because Bulma was busy.
Once he had it, he was delighted. To him, icecream was the closest thing to PUDDING, and he had an entire bucket all to himself. He immediately came up with an excuse and scurried out of sight, behind the lookout tower. He quickly began to much on the icecream, getting a headache but not caring. However, the headache clouded his mind from what was actually happening. The icecream WAS Majin Buu, back for revenge after being rekt, ravaged, humiliated and YEETED into the ocean over a cup of pudding. To him, he made candy like that ALL THE TIME, but a scrawny cat wasn't about to tell him to fork over all that pudding!
By the time he'd act, Beerus would already have eaten ALL of the icecream.

"Mmmm. Delicious... but is it always this sticky? I know it's bubblegum flavored, but..." He asked as he took a piece out and began stretching his fingers apart. It was rubbery, and melting down his hand. For that matter, it started MOVING. The icecream quickly covered his hand and began to explode in size around him!
"WHAT THE??? WHAT IS THIS?! THIS ICECREAM IS ALIVE! HAKA-" The Hakaishin was about to obliterate it, when the icream he already ate rose up from within and began taking him over from inside. His mouth was too full of the sticky fluid to utter his destruction move. He had fallen right into Buu's prank!

The majin laughed from inside the bucket as his body began spreading and taking over the irate God of Destruction. Now the God of being pranked. He squirmed and wiggled around, trying to get it out, but his arms were already taken over! He was too proud to call for help!
"How?! HOW WAS I PUNKED BY THAT CHEAP MAJIN?!" He yelled as a head tentacle, and tail tentacle resembling Buu's own formed on his body, and a Majin collar over his upper attire to match; a sign of absolute domination by the pink pudge of power.
"Well played Majin, but I will NOT let you get away with this. Destroying you would be a KINDNESS!" The god of destruction yelled before wrestling and pulling at the slime.
He'd be like that for 1 week, and since Buu can disguise himself, Whis would never notice... or so he thought. That's how long Buu wanted his revenge to last.

In all actuality, Whis already knew this was coming, and decided to "coincidentally" stop by Goku's house to see what Chi Chi was cooking. He was actually watching the whole thing on his staff, laughing hysterically at the prank.