Royal Cinderella Mama - I Was Reincarnated as a Poverty-Stricken Woman but an Emperor Became Infatuated with Me!?

Did I reincarnate as a peasant woman? Or maybe a saint? Somehow I met the cool-headed emperor at the dirty imperial palace. He becomes infatuated with me and I climb my way up the royal social ladder!
My normal everyday life used to consist of my job, that didn’t depend on me and my hobby, gardening. It’s a modest lifestyle of living alone. Then one day, I open a door to another world-
I suddenly realized that there was an open air bath! After I broke off from some naked man and gathered my surroundings, I found out that I am Rosalind, the daughter of a ruined noble. I have absolutely no money, but if I can raise my favorite plants and make some money, I will persist and keep on living in this world.
I come from a low social standing so there is the chance I’ll be harassed, but this mysterious man - Alexander - whose origins are unknown, has been taking care of me. Who exactly is he?