The accessory quest thread is here: https://harem-battle.club/kamihime-p...ry-quests.html
Please ask any questions relating to accessory quests there instead of making new threads.

Once you have 25-30Kish overall ATK and an assault grid of at least 70% or more, you should be able to easily do rank 1-4 accessory quests. If you got wiped out on rank 1, you have a looong way to go. Just keep improving your grids.