Torii no Mukō wa, Shiranai Sekai Deshita

After losing her mother and feeling out of place in her non-blood-related family, our protagonist Chitose one day passes through a mysterious torii gate and finds herself lost in Senkoku, a world different from modern Japan. There she meets Rei, a handsome immortal who runs a botanical garden. At first, Chitose is confused, but after meeting the mysterious young man Tori and being touched by the kindness of the people of this world, her wounded heart begins to heal...

This is a heartwarming fantasy story that depicts Chitose's struggle to become a pharmacist in a somewhat Chinese-style alternate world, and her interactions with the handsome men who surround her.

(Source: Kodansha, translated)