Warning: Spoilers Off applies to these pages. Proceed at your own risk.

Fire and Ice

Jack blames baby Ace for him breaking the "no-believers" rule on the other world. Baby Ace just giggles happily at him.
Jack gets Sabo to believe in him by throwing a snowball into his face.
After a heartwarming and serious discussion whether having fire powers may hurt Jack, Ace takes a bite of the Mera Mera no Mi and turns green. Jack nearly rolls into the ocean from laughter.
Jack says he supposes he will have to trust Ace with his own safety occasionally. Ace isn't sure whether he should appreciate the gesture or be insulted.
Marco does not believe Ace's "Wintery Guardian Angel" exists. He instantly slips on some ice and falls on his butt.

Embers and Frost

Tooth remains calm when a Marine insults Jack... until he insults Jack's teeth. Then she punches him in the face, knocking him out.
Ace draws a pineapple and claims it's Marco. He even draws Marco's eyes on it.
Jack randomly throws snowballs at Sabo to "teach him to dodge". Sabo is hit every time.
Law most definitely does not care about Baby Tooth. Nor does he growl over-protectively when Luffy almost swats her. And he also does not think she is adorable.
The mental image of Law having a tiny, cheerful fairy on his hat is side-splitting enough on its own.
Bunny is explosively angry that his bounty is a measly 200 Beri because the World Government believes he is a pet.

Funny / Summer and Winter