If you were looking for a different "Classmate" story with actual romantic development, you may be thinking of: Enslavement Magic - My Classmate is a Princess Knight Wiki

The relationships in this series are largely defined by a dark, non-consensual power dynamic rather than traditional romance.

: The central storyline focuses on the irony of Toru enslaving Kirika, a girl he once admired from afar as a "beautiful girl with a kind heart" back in their original world. Alternative Titles with Similar Names

: Toru views the women he captures, including village girls and adventurers, primarily as "toys" or tools for his war potential.

: A key turning point occurs when Toru’s magic reaches Level 6, allowing him to restore his slaves' original personalities. However, the magic remains absolute: they must still serve and respect him as their master, creating a paradoxical dynamic where they have their old selves back but are magically compelled to be obedient.

Based on the title provided, you are likely referring to the adult isekai series (also known as My Classmate is a Princess Knight or My Slave IS Classmate in some translations). This series revolves around Tōru Odamori , a "Slavemancer" who builds a harem by magically dominating women in a fantasy world, including his former class president, Kirika . Core Romantic and Relationship Dynamics