It's been a few weeks since the mews met, their not having a good bonding per say. We can see Mewtwo pushing back Mew from hugging him.

"Enough of this, I'm not any "child" of yours!!" He yelled,

...

Few minutes later, Y/N gets back from over watch duty as he stopped and sees Mewtwo in what appears to be a... bubble.

"Uh, did you put Mewtwo in time-out?"

"Mew!"

Mewtwo looks back at Y/N with a hating look.

"Quiet you.."💢

Y/N couldn't help but chuckle.

Ding!