fiancé; fiancée
Borrowed from French; used for a person one is engaged to marry. Gender is not distinguished in Japanese spelling.
from French fiancé(e)
彼女は私のフィアンセです。
She is my fiancée.
フィアンセと結婚式の準備をしている。
I'm preparing for the wedding with my fiancé.
She introduced me to her friend's fiancée.
He'll become my fiancé next month.
She quit her job in order to marry her fiancé.