Imperial Bride by C.J. Scarlett

Hating her isolated, sheltered life in the Japanese Imperial Family Maiko longs for action and adventure among the stars. When her opportunity come, she grabs it with both hands and risks everything to protect her new home world when a temporal anomaly threatens to swallow everything in its path.
Little does she know her father has made an exception to the longstanding rule that no Imperials leave Earth, only because he plans to have her fitted with new husband from the Krylon Imperial House. There are two brothers. She has her heart set on the scarred one with curious eyes. Unfortunately, arrangements were made for her to be courted by the one with a smirking face, snarky attitude, and reputation for running around the galaxy chasing women.

No thank you dies on her lips about the time he hits her with their very first kiss. A handsome clone from a nearby world seems mesmerized by her intelligence and charm. He would be a much better fit, since he’s not been caught cavorting in the harems but something is missing when they are together.
It all may become a moot issue unless they can figure out how to stop the darkness from swallowing their world.