Various sidequests are within the game. They consist of completing different kinds of objectives for a items, skills, character recruitment, and so on.
They are not required to reach an ending.
Akyuu's Item Acquisitions
Sakuya's Missing Items
Cake for the Mistress
Mineral Dispute and Silver Bamboo
Temporary Peace Between Immortals
Buddhist Priest and Sailor
Quest for the (Repair of the) Holy Grail
The Judge and the Shinigami
Meeting the Great Tengu
Showdown Against Yuuka
Clock Tower Disturbance
Beyond the Tower's Basement
The Old Emissary
Enter the Abyss (Major)
Conflict Within Nameless Hill
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