Ane no Migawari de Totsuida Nokorikasu Reijou desu ga, Shiawase Sugiru Fuhai Seikatsu wo Okurimasu

Magritte, the second daughter of Viscount Nefershall, lacks magical abilities and was raised as a servant by her older sister, who referred to her as "leftovers." Despite this, she remains cheerful, enjoying life through cooking and memories of a past existence. When her sister flees, Magritte takes her place and marries her sister's fiancé, Marquis Ganongoulf. The Marquis is feared for his rumored "corruption magic," but Magritte is unfazed. Rather than being frightened, she appears genuinely eager to encounter his magic.