She was one of astronaut in Dr stone
Her husband is Yakov Nikitin
She's from Russia 
She is a ISS crew member of Byakuya ishigami and his friends
Her best friend is Connie lee, and shamil volkov and Lillian Weinberg is also her friend too

She's witnessing pertification on earth
She with the ISS crew living in treasure island after pertification, and she's having two kids with Yakov

Six years later, Darya and Yakov go to mainland for antibiotics for Connie, and they're both died because drowned

Lillian is a popular singer from America
And she's was an astronaut in ISS with byakuya, Connie, shamil, darya, and Yakov
Connie is one of big fan of her

She's selling 10 milion CDs at this time
And she's was a diva too
Her songs are One small step, wont give up, and trash is treasure 

She's witnessing pertification on earth
After that, she in treasure island with ISS crew, and shes taking care of the children
And probably she's died because of pneumonia 

Yakov is a Russian Middle-aged man who joins ISS crew in space
His wife is Darya Nikitina
And he's with Byakuya ishigami, Lillian Weinberg, Shamil volkov, Connie Lee and his wife in ISS

He's witnessed the pertification on earth
And lives in treasure island after that
Later... He's died with his wife because drowned when go to mainland for Connie's antibiotics 

His enemy are Connie Hitam

Shamil is one of ISS astronaut crew besides byakuya, Connie (his wife), Lillian, Darya, Yakov

He was a cosmonaut and pilot before he's became an astronaut
He's from Russia, and married to Connie
He died from pneumonia after mourning his wife

He seen pertification on earth from space with another crews

Connie was ISS crew member with byakuya, Lillian, Shamil, Darya, and Yakov
She's from America (maybe she's having Chinese gen)
Her husband is shamil volkov 
 She was Lillian Weinberg (singer) big fan

She witnessed the pertification on earth, and lives in treasure island with the crews, later... She died because pneumonia 