Becoming Stronger Begins with Frozen

The currently selected worlds are Frozen - Origin of the White Snake - Ace Censor - other worlds to be determined. Are there any worlds that can be mentioned and considered? The protagonist travels through Frozen and becomes Elsa's brother. He unexpectedly obtains Elsa's ice power and becomes stronger from then on... The time travel is all in the world of animation. This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.