Mezase! Kakkoii 1-nensei: Champion ni Chousen

Overview

Kitsu, Korasho and Rakki are playing football on the school yard when a quarrel between Kitsu and Takero emerges. Witnessing this, the green frog abducts all four to an alternate reality. Rakki, however, is quickly separated from the other three, causing them to go on a search for her. The three wander through this world they are trapped in and are faced with increasingly difficult challenges. First they meet the walking stationery, then they come across Kotoba Princess and as their final challenge they found themselves faced up against Sansuu Robo Super. On the brink of losing, Kitsu and Takero see themselves forced to reconcile their earlier differences and unite their strengths.

Source: AniList