Tokyo in the near future. The rich live in the sky to avoid disasters and epidemics.
NOUNAI Senri joins RUOWA, a large company in the sky, to cure his sister's incurable disease, but his body becomes weak after he takes RUOWA Metal, the company's drink.
NOUNAI SenrI is looking for information on the daughter of the last user, security guard TAKAYAMA, in DATE's lab.
TAKAYAMA Ellie lives alone in the basement