Shiitage Rareta ma Dougushi wa Mob Shitsuji to Kakeochi Suru

I never expected the dull butler to actually be a prince...! Erin, a young girl who devotes herself to developing magical tools to fulfill her late mother’s dream of "making people happy with magic tools." However, as the child of a mistress, Erin is in a difficult position and endures relentless harassment from her stepmother. Despite her struggles to achieve her dream, Erin's hopes are crushed by her stepmother's schemes, and she is pushed to the depths of despair. In her darkest moment, the only ally she has, the butler Foolda, reaches out to her. "Would you elope with me?"