Just a magical girl who picks up trash

When his life came to an end, Yu Huan suddenly felt that the world before his eyes had undergone earth-shaking changes!
The unchanging ward turned into a dilapidated ruin?!
The friendly doctor turned into a flame-breathing monster?!
Even her frail body has transformed into a vibrant loli? !
He didn't die? She traveled through time!
However... in the ruins where strange beasts and demons roam everywhere, how can a little Lolita like me, who is powerless, realize her dream of traveling around the world?
"Ding~~ The scavenging system is at your service!"