"The Nine Mortal Sins" is a novel by Anton Emelyanov and Sergey Savinov, the first book of the eponymous cycle. Genre: action fantasy, people who end up in magical worlds (isekai), “boyar-anime.”
Manuel de Luna has always been good at hiding. Often, people simply didn’t notice him as they passed by. But he himself always saw what others tried to conceal. Traps, stolen wine, secrets from the past… In general, not much of a gift, considering that the power of his bloodline still hasn’t awakened in him. Other hidalgos were already mastering purity and fighting corruption, while he could only rely on his sword. But will that matter when the sky again starts dropping celestial stones, and the hearts of the undead hidden inside them grant new abilities to the human line? Soon the rulers of liches, ghouls, and even bone dragons will begin their path. And wild undead are also eager to spread across the kingdom’s lands — but for some reason, the purity that worked so well against corruption creatures doesn’t work on them at all.