Heroine? Saint? No, I'm an All-Works Maid!

'''Heroine? Saint? No, I'm an All-Works Maid!''' is a reincarnation isekai.

Ritsuko Mizunani is a brilliant child from Japan, who could advance any field of science she chose; despite this, she is obsessed with becoming the perfect maid. She dies in a plane crash on the way to England to train, being reborn in another world as Celesti McMurden and retains her same brilliance and passion. After the death of her mother Serene, she learns in the will that her father is Count Cloud Reginbass; the two were in love but Cloud's father wouldn't have it. Knowing there's no way the Count would let her follow her dream, Celesti decides against contacting him and promises herself and mother's memory that she would become the best maid ever; using magic to look Japanese again and changing her name to Melody Wade.

Trivia

 * Melody has no clue that she reincarnated as the heroine of the otome game Silver Saint and the Five Oaths; luckily her precaution against being recognized helped her evade knights her father sent to look for mother, and her by extension, paid off.
 * Melody awakened the Saint powers by making a vow to be a great maid and to honor her mother, rather the otome game plot where Celesti makes the vow to her love interest a long time after Serene's death. The world was set up to grant the powers when the heroine made "a vow to self and another".
 * The reason Melody got sucked into the otome game world appears to be due to interacting with two fans of the game prior to her plane crash.
 * The two are reincarnated as the first prince and villainess, and are trying desperately to get the game on track. Unaware Melody broke the script by gaining the Saint powers early, and refusing her noble lineage.
 * The plot of the Otome game keeps dragging Melody in against her will.
 * It may be God doing so, seeing as it's narration shows utter exasperation at Melody being so dense.
 * Melody prevents the rise of the Demon King out of sheer obviousness. Melody gave friendship and acknowledgement to her lady Lucinia, keeping from jealous anger that would have attracted its spirit and made her its vessel. The Demon King possessed a cat and found Melody by chance, coming to enjoy her gentle affection and being purified into pet for Lucinia from it.