Flee, My Elven Ninja! 3D

You're the ninja sent to rescue an imprisoned elf named Lizet, except rescuing her isn't enough. The world's too dangerous for that, so you take it on yourself to train her in ninjutsu instead of just carrying her out.

That training is the game's actual hook: a captured elven maiden turned apprentice, with the world outside still working against both of you.

Combat runs turn-based while you build up Lizet's skills, with a sandbox structure loose enough to move between training sessions and whatever else the day calls for. The harem framing and the rest of the cast fold into that same loop rather than sitting off to the side as separate content.