Apparently, even a mimic would do anything for a Klondike bar. However, seeing as you never asked for anything, he instead burps up the gnomes given to him earlier. They slide out his mouth, fall on the floor and say, "Mimic insides are like Slip'n'slides. But 20 times better!" They then jump back in, leaving their cool hats for you to take, even if they don't fit you.

I give the mimic a rose.

After practically inhaling the blanket, the Mimic engages in a brief coughing fit. It hacks like a cat with a hairball until something erupts inside of it with a grumbling sound. The Mimic then spits out a large origami crane made of glass. 

I toss in a piece of chewing gum. 

"Chew chew chewing gum.  Chew chew chewing gum is fun fun fun." The mimic sings while joyfully smacking it's lips.  It then belches out a one-year subscription to D&D Beyond.

I flick a pebble into the mimic's mouth.  

"This Pizza is fantabulous!!" the mimic yells as he had never tasted pineapple before. He then begins chasing you around the room with his new arms and legs wanting more...

"Feeeeed meeeee MOAR!!!"

I give him roller skates :p

the mimic munches the funny glasses .It burbles happily. 

with a raucous burp the mimic brings forth a full set of AD&D books it's been saving for decades, hoping for just the right buyer. 

I feed the mimic my left arm.

the mimic is unhappy with your choice in vehicle. it pushes the alarm button then swallows the keys, leaving the honking in the distance. 

the mimic spouts some interesting dialogue about the interplay between consumerism and identity. 

I feed the mimic the communist manifesto. 

The mimic gulps your communist manifesto and burps out a leather briefcase containing Marcellus Wallace's soul.

Jules and Vincent bust through the door...Roll Initiative. :P

I throw the mimic a tasty Big Kahuna burger.

The mimic licks it's chops and gulps down the fry bits in one hearty bite and spits out a beating heart. Based off of its anatomy you know it is not the heart of the mimic itself nor that of the gnome inside of it, however you cannot determine from which species it is from. How it is still beating you are also unsure.

I feed the mimic Adohand's Ear Stew (recipe on the Adohand's Cookbook page) and the plentiful bowl I put it in to ensure I never ran out.

The mimic swallows the sailor moon figure, attempting to change its shape to match.  It spits out several magical girl outfits and seems to want an opinion on which to wear.

I feed the mimic a prominent political figure.

*Insert Figure's name here* is eaten whole by the mimic. However, the mimic seems to have gone orange, and he keeps saying, "We need to build a wall" in an annoying voice. Without even stopping, the mimic gives you a Pokeball covered in... Something warm, wet and acidic.

As well as offering the mimic a camera, I let him know that he should wear the purple magic girl outfit. It's my favorite colour. *Wink*

The mimic scoffs at the idea of wearing stinky clothes and gobbles up the camera.  The camera flashes a few times before disappearing down it's throat.  Down floats a small picture of you and the mimic with the words, "To my best fan!" signed, Cage. 

I toss Kirby into the mimic's mouth.  

In a vortex of wind Kirby consumes the mimic and the entire contents of it's belly.  This game now becomes Feed the Kirby.

I feed Kirby my gamecube copy of super smash bros. :)

Kirby spits out a mimic colored Yoshi and a Yoshi colored mimic, who begin a fight to the death.

I feed Kirby a bubbled gem shard.