Ookii Onna no Ko ni Hakobareru!

The four main characters, Ichika, Shinome, and Rena, are trapped in another world that resembles a school by chance. Moreover, the main character is minimized and naked for some reason.

I can't run with a small stride. On top of that, Ichika, who can't see the protagonist freezing in the cold, "can't help it" and offers to explore while holding the protagonist...

[From DL Site]