Part 2 of "The Chosen One" Yukina was in grief because of her lost memories. She wasn't contented to the fact that the only thing she knew is Luka being her lover in the past and will be in the future. With the duras and zweilts fighting how can she regain her memories? and her everything.
Don't postpone what you want. Don't leave anything misunderstood. Make sure the people you care about know; make sure they know how you really feel. Because just like that, it could end. He's reckless and indignant. She harbors an all-consuming secret. Sometimes, God gives us what we never knew we needed.