After years of friendship with the slime girl Puniru, middle schooler Kotaro struggles to deal with her shape-shifting charms — and his feelings.

Cursed as a child to never have an heir, Prince Oscar seeks the continent's most powerful witch, Tinasha, hoping she'll break his curse. To meet her, he'll have to climb her formidable tower, which grants a wish to whoever reaches the top.

Rud raids the treacherous labyrinths, uninterested in fabled riches but desperate to cure his sick sister. Kicked out by a conceited hero, Rud heads home empty-handed until he rescues a girl who exposes his unparalleled protection.