Maimiko Touko no Jikenbo

From Storm in Heaven:

Touko Hanamori is the young successor to the Hanamori family's line of priestesses. What she longs for, however, is to have a normal life–to have a boyfriend, go on dates, and live like a normal girl would. A new job introduces her to a handsome young man, but will this be the start of a blooming romance…or is there something she doesn't yet realize?