The Demon King’s Daughters

The Demon King, sealed away for years, is back, and his clan feels no pain and shows less mercy while they carve up a land that had gotten used to peace. His daughters are the ones doing the actual conquering, planting strongholds region by region while goblins soften up the resistance for them.

You're the resistance, pushing back the goblin lines stage by stage to track down where the Demon King is hiding, with the endgame being to run him down and end the whole invasion outright.

The core of it is tower-defense strategy: pick towers, place them, hold the line as spawns scale up through the later stages, with stage descriptions now spelling out what each new enemy or character actually does before you meet them. Losing ground against the daughters plays out in the expected corruption and rape scenes, but the loop underneath is still counting spawns and managing lanes, not clicking through a visual novel.