Jetter Mars and Tamao

Hey look! 

Jetter Mars was having a fantastic Field Trip to the Cave! 

Seems to me Jetter Mars was wearing a Backpack 

without wearing any Clothes, 

but Tamao was wearing a Backpack 

with wearing any Clothes 

from Jetter Mars Episode called 

"The Samurai Robot from the seventh Year of the Tenpō era". 

But Jetter Mars wants Shibugaki to be a Friend with him.