Misericorde: Volume One
https://www.youtube.com/watch?v=__QbQCn00XA
Misericorde is the first installment of a planned visual novel mystery about a 15th-century convent, which is to say, its dialogue is deeply moody with fantastic art that seems like it might have once been buried under coal. You arrive in the story after a murder.
“As an Anchoress, you took an oath to never leave your cell; to devote yourself entirely to God and provide spiritual support to all who came to your door,” the game’s Steam description says. “But as the only Sister who couldn’t possibly have committed the crime, you have a new mission: solve the case, before the bishop shutters the convent and the killer goes unpunished.”