Kouya no Hanayome

Synopsis

The story is set in the Stone Age. An unconscious woman is discovered by a family of foragers. In need of a bride, the eldest "son" (actually a daughter) decides to marry her. Hunting mammoths, singing, dancing, taking a nap, occasionally going to hot springs. This is the daily life of Stone Age girls who are living comfortably in the period before the Ice Age. (Source: AniList)