Yuwakashi Yuusha no Fukushuutan – Mizu o Oyu ni Suru Koto Shika Dekinai Yuusha Dakedo, Subete o Ubatta Omaera o Korosu niwa Koitsu de Juuban da

A Hero is someone chosen by God to receive a supernatural ’gift’. A unique existence, only one Hero can exist at a time, with a new one being chosen upon the former’s death.
This generation’s Hero is a ordinary villager girl named Kyrie whose gift is merely being able to boil water.
When her family and friends are slaughtered, Kyrie is backed into a corner and learns the true value of that boiling hot power, and how well it could be used to fan the flames of revenge that burned inside of her.